docs(aio): move quickstarts and glossary into guide

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@description
Good tools make application development quicker and easier to maintain than
if you did everything by hand.
The [**Angular CLI**](https://cli.angular.io/) is a **_command line interface_** tool
that can create a project, add files, and perform a variety of ongoing development tasks such
as testing, bundling, and deployment.
The goal in this guide is to build and run a simple Angular
application in TypeScript, using the Angular CLI
while adhering to the [Style Guide](guide/guide/style-guide) recommendations that
benefit _every_ Angular project.
By the end of the chapter, you'll have a basic understanding of development with the CLI
and a foundation for both these documentation samples and for real world applications.
You'll pursue these ends in the following high-level steps:
1. [Set up](guide/cli-quickstart#devenv) the development environment.
2. [Create](guide/cli-quickstart#create-proj) a new project and skeleton application.
3. [Serve](guide/cli-quickstart#serve) the application.
4. [Edit](guide/cli-quickstart#first-component) the application.
And you can also <a href="/resources/zips/cli-quickstart/cli-quickstart.zip">download the example.</a>
<h2 id='devenv'>
Step 1. Set up the Development Environment
</h2>
You need to set up your development environment before you can do anything.
Install **[Node.js® and npm](https://nodejs.org/en/download/)**
if they are not already on your machine.
~~~ {.l-sub-section}
**Verify that you are running at least node `6.9.x` and npm `3.x.x`**
by running `node -v` and `npm -v` in a terminal/console window.
Older versions produce errors, but newer versions are fine.
~~~
Then **install the [Angular CLI](https://github.com/angular/angular-cli)** globally.
<code-example language="sh" class="code-shell">
npm install -g @angular/cli
</code-example>
<h2 id='create-project'>
Step 2. Create a new project
</h2>
Open a terminal window.
Generate a new project and skeleton application by running the following commands:
<code-example language="sh" class="code-shell">
ng new my-app
</code-example>
~~~ {.l-sub-section}
Patience please.
It takes time to set up a new project, most of it spent installing npm packages.
~~~
<h2 id='serve'>
Step 3: Serve the application
</h2>
Go to the project directory and launch the server.
<code-example language="sh" class="code-shell">
cd my-app
ng serve --open
</code-example>
The `ng serve` command launches the server, watches your files,
and rebuilds the app as you make changes to those files.
Using the `--open` (or just `-o`) option will automatically open your browser
on `http://localhost:4200/`.
Your app greets you with a message:
<figure class='image-display'>
<img src='assets/images/devguide/cli-quickstart/app-works.png' alt="The app works!"> </img>
</figure>
<h2 id='first-component'>
Step 4: Edit your first Angular component
</h2>
The CLI created the first Angular component for you.
This is the _root component_ and it is named `app-root`.
You can find it in `./src/app/app.component.ts`.
Open the component file and change the `title` property from _app works!_ to _My First Angular App_:
<code-example path="cli-quickstart/src/app/app.component.ts" region="title" linenums="false">
</code-example>
The browser reloads automatically with the revised title. That's nice, but it could look better.
Open `src/app/app.component.css` and give the component some style.
<code-example path="cli-quickstart/src/app/app.component.css" linenums="false">
</code-example>
<figure class='image-display'>
<img src='assets/images/devguide/cli-quickstart/my-first-app.png' alt="Output of QuickStart app"> </img>
</figure>
Looking good!
## What's next?
That's about all you'd expect to do in a "Hello, World" app.
You're ready to take the [Tour of Heroes Tutorial](guide/tutorial) and build
a small application that demonstrates the great things you can build with Angular.
Or you can stick around a bit longer to learn about the files in your brand new project.
## Project file review
An Angular CLI project is the foundation for both quick experiments and enterprise solutions.
The first file you should check out is `README.md`.
It has some basic information on how to use CLI commands.
Whenever you want to know more about how Angular CLI works make sure to visit
[the Angular CLI repository](https://github.com/angular/angular-cli) and
[Wiki](https://github.com/angular/angular-cli/wiki).
Some of the generated files might be unfamiliar to you.
### The `src` folder
Your app lives in the `src` folder.
All Angular components, templates, styles, images, and anything else your app needs go here.
Any files outside of this folder are meant to support building your app.
<aio-filetree>
<aio-folder>
src
<aio-folder>
app
<aio-file>
app.component.css
</aio-file>
<aio-file>
app.component.html
</aio-file>
<aio-file>
app.component.spec.ts
</aio-file>
<aio-file>
app.component.ts
</aio-file>
<aio-file>
app.module.ts
</aio-file>
</aio-folder>
<aio-folder>
assets
<aio-file>
.gitkeep
</aio-file>
</aio-folder>
<aio-folder>
environments
<aio-file>
environment.prod.ts
</aio-file>
<aio-file>
environment.ts
</aio-file>
</aio-folder>
<aio-file>
favicon.ico
</aio-file>
<aio-file>
index.html
</aio-file>
<aio-file>
main.ts
</aio-file>
<aio-file>
polyfills.ts
</aio-file>
<aio-file>
styles.css
</aio-file>
<aio-file>
test.ts
</aio-file>
<aio-file>
tsconfig.app.json
</aio-file>
<aio-file>
tsconfig.spec.json
</aio-file>
</aio-folder>
</aio-filetree>
<style>
td, th {vertical-align: top}
</style>
<table width="100%">
<col width="20%">
</col>
<col width="80%">
</col>
<tr>
<th>
File
</th>
<th>
Purpose
</th>
</tr>
<tr>
<td>
<code>app/app.component.{ts,html,css,spec.ts}</code>
</td>
<td>
Defines the `AppComponent` along with an HTML template, CSS stylesheet, and a unit test.
It is the **root** component of what will become a tree of nested components
as the application evolves.
</td>
</tr>
<tr>
<td>
<code>app/app.module.ts</code>
</td>
<td>
Defines `AppModule`, the [root module](guide/guide/appmodule) that tells Angular how to assemble the application.
Right now it declares only the `AppComponent`.
Soon there will be more components to declare.
</td>
</tr>
<tr>
<td>
<code>assets/*</code>
</td>
<td>
A folder where you can put images and anything else to be copied wholesale
when you build your application.
</td>
</tr>
<tr>
<td>
<code>environments/*</code>
</td>
<td>
This folder contains one file for each of your destination environments,
each exporting simple configuration variables to use in your application.
The files are replaced on-the-fly when you build your app.
You might use a different API endpoint for development than you do for production
or maybe different analytics tokens.
You might even use some mock services.
Either way, the CLI has you covered.
</td>
</tr>
<tr>
<td>
<code>favicon.ico</code>
</td>
<td>
Every site wants to look good on the bookmark bar.
Get started with your very own Angular icon.
</td>
</tr>
<tr>
<td>
<code>index.html</code>
</td>
<td>
The main HTML page that is served when someone visits your site.
Most of the time you'll never need to edit it.
The CLI automatically adds all `js` and `css` files when building your app so you
never need to add any `<script>` or `<link>` tags here manually.
</td>
</tr>
<tr>
<td>
<code>main.ts</code>
</td>
<td>
The main entry point for your app.
Compiles the application with the [JIT compiler](guide/glossary)
and bootstraps the application's root module (`AppModule`) to run in the browser.
You can also use the [AOT compiler](guide/glossary)
without changing any code by passing in `--aot` to `ng build` or `ng serve`.
</td>
</tr>
<tr>
<td>
<code>polyfills.ts</code>
</td>
<td>
Different browsers have different levels of support of the web standards.
Polyfills help normalize those differences.
You should be pretty safe with `core-js` and `zone.js`, but be sure to check out
the [Browser Support guide](guide/guide/browser-support) for more information.
</td>
</tr>
<tr>
<td>
<code>styles.css</code>
</td>
<td>
Your global styles go here.
Most of the time you'll want to have local styles in your components for easier maintenance,
but styles that affect all of your app need to be in a central place.
</td>
</tr>
<tr>
<td>
<code>test.ts</code>
</td>
<td>
This is the main entry point for your unit tests.
It has some custom configuration that might be unfamiliar, but it's not something you'll
need to edit.
</td>
</tr>
<tr>
<td>
<code>tsconfig.{app|spec}.json</code>
</td>
<td>
TypeScript compiler configuration for the Angular app (`tsconfig.app.json`)
and for the unit tests (`tsconfig.spec.json`).
</td>
</tr>
</table>
### The root folder
The `src/` folder is just one of the items inside the project's root folder.
Other files help you build, test, maintain, document, and deploy the app.
These files go in the root folder next to `src/`.
<aio-filetree>
<aio-folder>
my-app
<aio-folder>
e2e
<aio-file>
app.e2e-spec.ts
</aio-file>
<aio-file>
app.po.ts
</aio-file>
<aio-file>
tsconfig.e2e.json
</aio-file>
</aio-folder>
<aio-file>
node_modules/...
</aio-file>
<aio-file>
src/...
</aio-file>
<aio-file>
.angular-cli.json
</aio-file>
<aio-file>
.editorconfig
</aio-file>
<aio-file>
.gitignore
</aio-file>
<aio-file>
karma.conf.js
</aio-file>
<aio-file>
package.json
</aio-file>
<aio-file>
protractor.conf.js
</aio-file>
<aio-file>
README.md
</aio-file>
<aio-file>
tsconfig.json
</aio-file>
<aio-file>
tslint.json
</aio-file>
</aio-folder>
</aio-filetree>
<style>
td, th {vertical-align: top}
</style>
<table width="100%">
<col width="20%">
</col>
<col width="80%">
</col>
<tr>
<th>
File
</th>
<th>
Purpose
</th>
</tr>
<tr>
<td>
<code>e2e/</code>
</td>
<td>
Inside `e2e/` live the End-to-End tests.
They shouldn't be inside `src/` because e2e tests are really a separate app that
just so happens to test your main app.
That's also why they have their own `tsconfig.e2e.json`.
</td>
</tr>
<tr>
<td>
<code>node_modules/</code>
</td>
<td>
`Node.js` creates this folder and puts all third party modules listed in
`package.json` inside of it.
</td>
</tr>
<tr>
<td>
<code>.angular-cli.json</code>
</td>
<td>
Configuration for Angular CLI.
In this file you can set several defaults and also configure what files are included
when your project is build.
Check out the official documentation if you want to know more.
</td>
</tr>
<tr>
<td>
<code>.editorconfig</code>
</td>
<td>
Simple configuration for your editor to make sure everyone that uses your project
has the same basic configuration.
Most editors support an `.editorconfig` file.
See http://editorconfig.org for more information.
</td>
</tr>
<tr>
<td>
<code>.gitignore</code>
</td>
<td>
Git configuration to make sure autogenerated files are not commited to source control.
</td>
</tr>
<tr>
<td>
<code>karma.conf.js</code>
</td>
<td>
Unit test configuration for the [Karma test runner](https://karma-runner.github.io),
used when running `ng test`.
</td>
</tr>
<tr>
<td>
<code>package.json</code>
</td>
<td>
`npm` configuration listing the third party packages your project uses.
You can also add your own [custom scripts](https://docs.npmjs.com/misc/scripts) here.
</td>
</tr>
<tr>
<td>
<code>protractor.conf.js</code>
</td>
<td>
End-to-end test configuration for [Protractor](http://www.protractortest.org/),
used when running `ng e2e`.
</td>
</tr>
<tr>
<td>
<code>README.md</code>
</td>
<td>
Basic documentation for your project, pre-filled with CLI command information.
Make sure to enhance it with project documentation so that anyone
checking out the repo can build your app!
</td>
</tr>
<tr>
<td>
<code>tsconfig.json</code>
</td>
<td>
TypeScript compiler configuration for your IDE to pick up and give you helpful tooling.
</td>
</tr>
<tr>
<td>
<code>tslint.json</code>
</td>
<td>
Linting configuration for [TSLint](https://palantir.github.io/tslint/) together with
[Codelyzer](http://codelyzer.com/), used when running `ng lint`.
Linting helps keep your code style consistent.
</td>
</tr>
</table>
~~~ {.l-sub-section}
### Next Step
If you're new to Angular, continue on the
[learning path](guide/guide/learning-angular).
You can skip the "Setup" step since you're already using the Angular CLI setup.
~~~

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@title
Glossary
@intro
Brief definitions of the most important words in the Angular vocabulary.
@description @description
Angular has its own vocabulary.
Most Angular terms are common English words
with a specific meaning within the Angular system.
This glossary lists the most prominent terms
and a few less familiar ones that have unusual or
unexpected definitions.
[A](guide/glossary#A) [B](guide/glossary#B) [C](guide/glossary#C) [D](guide/glossary#D) [E](guide/glossary#E) [F](guide/glossary#F) [G](guide/glossary#G) [H](guide/glossary#H) [I](guide/glossary#I)
[J](guide/glossary#J) [K](guide/glossary#K) [L](guide/glossary#L) [M](guide/glossary#M) [N](guide/glossary#N) [O](guide/glossary#O) [P](guide/glossary#P) [Q](guide/glossary#Q) [R](guide/glossary#R)
[S](guide/glossary#S) [T](guide/glossary#T) [U](guide/glossary#U) [V](guide/glossary#V) [W](guide/glossary#W) [X](guide/glossary#X) [Y](guide/glossary#Y) [Z](guide/glossary#Z)
{@a aot}
## Ahead-of-time (AOT) compilation
~~~ {.l-sub-section}
You can compile Angular applications at build time.
By compiling your application<span if-docs="ts"> using the compiler-cli, `ngc`</span>, you can bootstrap directly
to a<span if-docs="ts"> module</span> factory, meaning you don't need to include the Angular compiler in your JavaScript bundle.
Ahead-of-time compiled applications also benefit from decreased load time and increased performance.
~~~
## Annotation
~~~ {.l-sub-section}
In practice, a synonym for [Decoration](guide/glossary#decorator).
~~~
{@a attribute-directive}
{@a attribute-directives}
## Attribute directives
~~~ {.l-sub-section}
A category of [directive](guide/glossary#directive) that can listen to and modify the behavior of
other HTML elements, attributes, properties, and components. They are usually represented
as HTML attributes, hence the name.
For example, you can use the `ngClass` directive to add and remove CSS class names.
Learn about them in the [_Attribute Directives_](guide/!{docsLatest}/guide/attribute-directives) guide.
~~~
## Binding
~~~ {.l-sub-section}
Usually refers to [data binding](guide/glossary#data-binding) and the act of
binding an HTML object property to a data object property.
Sometimes refers to a [dependency-injection](guide/glossary#dependency-injection) binding
between a "token"&mdash;also referred to as a "key"&mdash;and a dependency [provider](guide/glossary#provider).
~~~
## Bootstrap
~~~ {.l-sub-section}
You launch an Angular application by "bootstrapping" it using the application root Angular module (`AppModule`).
Bootstrapping identifies an application's top level "root" [component](guide/glossary#component),
which is the first component that is loaded for the application.
For more information, see the [Setup](guide/!{docsLatest}/guide/setup) page.
You can bootstrap multiple apps in the same `index.html`, each app with its own top-level root.
~~~
## camelCase
~~~ {.l-sub-section}
The practice of writing compound words or phrases such that each word or abbreviation begins with a capital letter
_except the first letter, which is lowercase_.
Function, property, and method names are typically spelled in camelCase. For example, `square`, `firstName`, and `getHeroes`. Notice that `square` is an example of how you write a single word in camelCase.
camelCase is also known as *lower camel case* to distinguish it from *upper camel case*, or [PascalCase](guide/glossary#pascalcase).
In Angular documentation, "camelCase" always means *lower camel case*.
~~~
{@a component}
## Component
~~~ {.l-sub-section}
An Angular class responsible for exposing data to a [view](guide/glossary#view) and handling most of the views display and user-interaction logic.
The *component* is one of the most important building blocks in the Angular system.
It is, in fact, an Angular [directive](guide/glossary#directive) with a companion [template](guide/glossary#template).
Apply the `!{_at}Component` !{_decoratorLink} to
the component class, thereby attaching to the class the essential component metadata
that Angular needs to create a component instance and render the component with its template
as a view.
Those familiar with "MVC" and "MVVM" patterns will recognize
the component in the role of "controller" or "view model".
~~~
## dash-case
~~~ {.l-sub-section}
The practice of writing compound words or phrases such that each word is separated by a dash or hyphen (`-`).
This form is also known as kebab-case.
[Directive](guide/glossary#directive) selectors (like `my-app`) <span if-docs="ts">and
the root of filenames (such as `hero-list.component.ts`)</span> are often
spelled in dash-case.
~~~
## Data binding
~~~ {.l-sub-section}
Applications display data values to a user and respond to user
actions (such as clicks, touches, and keystrokes).
In data binding, you declare the relationship between an HTML widget and data source
and let the framework handle the details.
Data binding is an alternative to manually pushing application data values into HTML, attaching
event listeners, pulling changed values from the screen, and
updating application data values.
Angular has a rich data-binding framework with a variety of data-binding
operations and supporting declaration syntax.
Read about the following forms of binding in the [Template Syntax](guide/!{docsLatest}/guide/template-syntax) page:
* [Interpolation](guide/!{docsLatest}/guide/template-syntax).
* [Property binding](guide/!{docsLatest}/guide/template-syntax).
* [Event binding](guide/!{docsLatest}/guide/template-syntax).
* [Attribute binding](guide/!{docsLatest}/guide/template-syntax).
* [Class binding](guide/!{docsLatest}/guide/template-syntax).
* [Style binding](guide/!{docsLatest}/guide/template-syntax).
* [Two-way data binding with ngModel](guide/!{docsLatest}/guide/template-syntax).
~~~
{@a decorator}
{@a decoration}
## Decorator | decoration
~~~ {.l-sub-section}
A *function* that adds metadata to a class, its members (properties, methods) and function arguments.
Decorators are a JavaScript language [feature](https://github.com/wycats/javascript-decorators), implemented in TypeScript and proposed for ES2016 (also known as ES7).
To apply a decorator, position it immediately above or to the left of the item it decorates.
Angular has its own set of decorators to help it interoperate with your application parts.
The following example is a `@Component` decorator that identifies a
class as an Angular [component](guide/glossary#component) and an `@Input` decorator applied to the `name` property
of that component. The elided object argument to the `@Component` decorator would contain the pertinent component metadata.
```
@Component({...})
export class AppComponent {
constructor(@Inject('SpecialFoo') public foo:Foo) {}
@Input() name:string;
}
```
The scope of a decorator is limited to the language feature
that it decorates. None of the decorations shown here will "leak" to other
classes that follow it in the file.
~~~ {.alert.is-important}
Always include parentheses `()` when applying a decorator.
~~~
~~~
## Dependency injection
~~~ {.l-sub-section}
A design pattern and mechanism
for creating and delivering parts of an application to other
parts of an application that request them.
Angular developers prefer to build applications by defining many simple parts
that each do one thing well and then wiring them together at runtime.
These parts often rely on other parts. An Angular [component](guide/glossary#component)
part might rely on a service part to get data or perform a calculation. When
part "A" relies on another part "B," you say that "A" depends on "B" and
that "B" is a dependency of "A."
You can ask a "dependency injection system" to create "A"
for us and handle all the dependencies.
If "A" needs "B" and "B" needs "C," the system resolves that chain of dependencies
and returns a fully prepared instance of "A."
Angular provides and relies upon its own sophisticated
dependency-injection system
to assemble and run applications by "injecting" application parts
into other application parts where and when needed.
At the core, an [`injector`](guide/glossary#injector) returns dependency values on request.
The expression `injector.get(token)` returns the value associated with the given token.
A token is an Angular type (`OpaqueToken`). You rarely need to work with tokens directly; most
methods accept a class name (`Foo`) or a string ("foo") and Angular converts it
to a token. When you write `injector.get(Foo)`, the injector returns
the value associated with the token for the `Foo` class, typically an instance of `Foo` itself.
During many of its operations, Angular makes similar requests internally, such as when it creates a [`component`](guide/glossary#component) for display.
The `Injector` maintains an internal map of tokens to dependency values.
If the `Injector` can't find a value for a given token, it creates
a new value using a `Provider` for that token.
A [provider](guide/glossary#provider) is a recipe for
creating new instances of a dependency value associated with a particular token.
An injector can only create a value for a given token if it has
a `provider` for that token in its internal provider registry.
Registering providers is a critical preparatory step.
Angular registers some of its own providers with every injector.
You can register your own providers.
Read more in the [Dependency Injection](guide/!{docsLatest}/guide/dependency-injection) page.
~~~
{@a directive}
{@a directives}
## Directive
~~~ {.l-sub-section}
An Angular class responsible for creating, reshaping, and interacting with HTML elements
in the browser DOM. The directive is Angular's most fundamental feature.
A directive is usually associated with an HTML element or attribute.
This element or attribute is often referred to as the directive itself.
When Angular finds a directive in an HTML template,
it creates the matching directive class instance
and gives the instance control over that portion of the browser DOM.
You can invent custom HTML markup (for example, `<my-directive>`) to
associate with your custom directives. You add this custom markup to HTML templates
as if you were writing native HTML. In this way, directives become extensions of
HTML itself.
Directives fall into one of the following categories:
* [Components](guide/glossary#component) combine application logic with an HTML template to
render application [views](guide/glossary#view). Components are usually represented as HTML elements.
They are the building blocks of an Angular application.
* [Attribute directives](guide/glossary#attribute-directive) can listen to and modify the behavior of
other HTML elements, attributes, properties, and components. They are usually represented
as HTML attributes, hence the name.
* [Structural directives](guide/glossary#structural-directive) are responsible for
shaping or reshaping HTML layout, typically by adding, removing, or manipulating
elements and their children.
~~~
## ECMAScript
~~~ {.l-sub-section}
The [official JavaScript language specification](https://en.wikipedia.org/wiki/ECMAScript).
The latest approved version of JavaScript is
[ECMAScript 2016](http://www.ecma-international.org/ecma-262/7.0/)
(also known as "ES2016" or "ES7"). Many Angular developers write their applications
in ES7 or a dialect that strives to be
compatible with it, such as [TypeScript](guide/glossary#typescript).
Most modern browsers only support the much older "ECMAScript 5" (also known as "ES5") standard.
Applications written in ES2016, ES2015, or one of their dialects must be [transpiled](guide/glossary#transpile)
to ES5 JavaScript.
Angular developers can write in ES5 directly.
~~~
## ES2015
~~~ {.l-sub-section}
Short hand for [ECMAScript](guide/glossary#ecmascript) 2015.
~~~
## ES5
~~~ {.l-sub-section}
Short hand for [ECMAScript](guide/glossary#ecmascript) 5, the version of JavaScript run by most modern browsers.
~~~
## ES6
~~~ {.l-sub-section}
Short hand for [ECMAScript](guide/glossary#ecmascript) 2015.
~~~
{@a F}
{@a G}
{@a H}
## Injector
~~~ {.l-sub-section}
An object in the Angular [dependency-injection system](guide/glossary#dependency-injection)
that can find a named dependency in its cache or create a dependency
with a registered [provider](guide/glossary#provider).
~~~
## Input
~~~ {.l-sub-section}
A directive property that can be the *target* of a
[property binding](guide/!{docsLatest}/guide/template-syntax) (explained in detail in the [Template Syntax](guide/!{docsLatest}/guide/template-syntax) page).
Data values flow *into* this property from the data source identified
in the template expression to the right of the equal sign.
See the [Input and output properties](guide/!{docsLatest}/guide/template-syntax) section of the [Template Syntax](guide/!{docsLatest}/guide/template-syntax) page.
~~~
## Interpolation
~~~ {.l-sub-section}
A form of [property data binding](guide/glossary#data-binding) in which a
[template expression](guide/glossary#template-expression) between double-curly braces
renders as text. That text may be concatenated with neighboring text
before it is assigned to an element property
or displayed between element tags, as in this example.
<code-example language="html" escape="html">
<label>My current hero is {{hero.name}}</label>
</code-example>
Read more about [interpolation](guide/!{docsLatest}/guide/template-syntax) in the
[Template Syntax](guide/!{docsLatest}/guide/template-syntax) page.
~~~
{@a jit}
## Just-in-time (JIT) compilation
~~~ {.l-sub-section}
A bootstrapping method of compiling components<span if-docs="ts"> and modules</span> in the browser
and launching the application dynamically. Just-in-time mode is a good choice during development.
Consider using the [ahead-of-time](guide/glossary#aot) mode for production apps.
~~~
## kebab-case
~~~ {.l-sub-section}
See [dash-case](guide/glossary#dash-case).
~~~
## Lifecycle hooks
~~~ {.l-sub-section}
[Directives](guide/glossary#directive) and [components](guide/glossary#component) have a lifecycle
managed by Angular as it creates, updates, and destroys them.
You can tap into key moments in that lifecycle by implementing
one or more of the lifecycle hook interfaces.
Each interface has a single hook method whose name is the interface name prefixed with `ng`.
For example, the `OnInit` interface has a hook method named `ngOnInit`.
Angular calls these hook methods in the following order:
* `ngOnChanges`: when an [input](guide/glossary#input)/[output](guide/glossary#output) binding value changes.
* `ngOnInit`: after the first `ngOnChanges`.
* `ngDoCheck`: developer's custom change detection.
* `ngAfterContentInit`: after component content initialized.
* `ngAfterContentChecked`: after every check of component content.
* `ngAfterViewInit`: after a component's views are initialized.
* `ngAfterViewChecked`: after every check of a component's views.
* `ngOnDestroy`: just before the directive is destroyed.
Read more in the [Lifecycle Hooks](guide/!{docsLatest}/guide/lifecycle-hooks) page.
~~~
## Module
~~~ {.l-sub-section}
~~~ {.alert.is-important}
Angular has the following types of modules:
- [Angular modules](guide/glossary#angular-module).
For details and examples, see the [Angular Modules](guide/!{docsLatest}/guide/ngmodule) page.
- ES2015 modules, as described in this section.
~~~
A cohesive block of code dedicated to a single purpose.
Angular apps are modular.
In general, you assemble an application from many modules, both the ones you write and the ones you acquire from others.
A module *exports* something of value in that code, typically one thing such as a class;
a module that needs that class *imports* it.
The structure of Angular modules and the import/export syntax
is based on the [ES2015 module standard](http://www.2ality.com/2014/09/es6-modules-final.html).
An application that adheres to this standard requires a module loader to
load modules on request and resolve inter-module dependencies.
Angular doesn't include a module loader and doesn't have a preference
for any particular third-party library (although most examples use SystemJS).
You can use any module library that conforms to the standard.
Modules are typically named after the file in which the exported thing is defined.
The Angular [DatePipe](https://github.com/angular/angular/blob/master/modules/@angular/common/src/pipes/date_pipe.ts)
class belongs to a feature module named `date_pipe` in the file `date_pipe.ts`.
You rarely access Angular feature modules directly. You usually import them from an Angular [scoped package](guide/glossary#scoped-package) such as `@angular/core`.
~~~
{@a N}
## Output
~~~ {.l-sub-section}
A directive property that can be the *target* of event binding
(read more in the [event binding](guide/!{docsLatest}/guide/template-syntax)
section of the [Template Syntax](guide/!{docsLatest}/guide/template-syntax) page).
Events stream *out* of this property to the receiver identified
in the template expression to the right of the equal sign.
See the [Input and output properties](guide/!{docsLatest}/guide/template-syntax) section of the [Template Syntax](guide/!{docsLatest}/guide/template-syntax) page.
~~~
## PascalCase
~~~ {.l-sub-section}
The practice of writing individual words, compound words, or phrases such that each word or abbreviation begins with a capital letter.
Class names are typically spelled in PascalCase. For example, `Person` and `HeroDetailComponent`.
This form is also known as *upper camel case* to distinguish it from *lower camel case* or simply [camelCase](guide/glossary#camelcase).
In this documentation, "PascalCase" means *upper camel case* and "camelCase" means *lower camel case*.
~~~
## Pipe
~~~ {.l-sub-section}
An Angular pipe is a function that transforms input values to output values for
display in a [view](guide/glossary#view).
Here's an example that uses the built-in `currency` pipe to display
a numeric value in the local currency.
<code-example language="html" escape="html">
<label>Price: </label>{{product.price | currency}}
</code-example>
You can also write your own custom pipes.
Read more in the page on [pipes](guide/!{docsLatest}/guide/pipes).
~~~
## Provider
~~~ {.l-sub-section}
A _provider_ creates a new instance of a dependency for the
[dependency injection](guide/glossary#dependency-injection) system.
It relates a lookup token to code&mdash;sometimes called a "recipe"&mdash;that can create a dependency value.
~~~
{@a Q}
## Reactive forms
~~~ {.l-sub-section}
A technique for building Angular forms through code in a component.
The alternative technique is [template-driven forms](guide/glossary#template-driven-forms).
When building reactive forms:
- The "source of truth" is the component. The validation is defined using code in the component.
- Each control is explicitly created in the component class with `new FormControl()` or with `FormBuilder`.
- The template input elements do *not* use `ngModel`.
- The associated Angular directives are all prefixed with `Form`, such as `FormGroup`, `FormControl`, and `FormControlName`.
Reactive forms are powerful, flexible, and a good choice for more complex data-entry form scenarios, such as dynamic generation of form controls.
~~~
## Router
~~~ {.l-sub-section}
Most applications consist of many screens or [views](guide/glossary#view).
The user navigates among them by clicking links and buttons,
and performing other similar actions that cause the application to
replace one view with another.
The Angular component router is a richly featured mechanism for configuring and managing the entire view navigation process, including the creation and destruction
of views.
~~~
## Router module
~~~ {.l-sub-section}
A separate [Angular module](guide/glossary#angular-module) that provides the necessary service providers and directives for navigating through application views.
For more information, see the [Routing & Navigation](guide/!{docsLatest}/guide/router) page.
~~~
## Routing component
~~~ {.l-sub-section}
An Angular [component](guide/glossary#component) with a `RouterOutlet` that displays views based on router navigations.
For more information, see the [Routing & Navigation](guide/!{docsLatest}/guide/router) page.
~~~
## Scoped package
~~~ {.l-sub-section}
A way to group related *npm* packages.
Read more at the [npm-scope](https://docs.npmjs.com/misc/scope) page.
Angular modules are delivered within *scoped packages* such as `@angular/core`,
`@angular/common`, `@angular/platform-browser-dynamic`, `@angular/http`, and `@angular/router`.
Import a scoped package the same way that you import a normal package.
The only difference, from a consumer perspective,
is that the scoped package name begins with the Angular *scope name*, `@angular`.
<code-example path="architecture/src/app/app.component.ts" linenums="false" title="architecture/ts/src/app/app.component.ts (import)" region="import">
</code-example>
~~~
## Service
~~~ {.l-sub-section}
For data or logic that is not associated
with a specific view or that you want to share across components, build services.
Applications often require services such as a hero data service or a logging service.
A service is a class with a focused purpose.
You often create a service to implement features that are
independent from any specific view,
provide shared data or logic across components, or encapsulate external interactions.
Applications often require services such as a data service or a logging service.
For more information, see the [Services](guide/!{docsLatest}/tutorial/toh-pt4) page of the [Tour of Heroes](guide/!{docsLatest}/tutorial/) tutorial.
~~~
{@a snake-case}
## snake_case
~~~ {.l-sub-section}
The practice of writing compound words or phrases such that an
underscore (`_`) separates one word from the next. This form is also known as *underscore case*.
~~~
{@a structural-directive}
{@a structural-directives}
## Structural directives
~~~ {.l-sub-section}
A category of [directive](guide/glossary#directive) that can
shape or reshape HTML layout, typically by adding and removing elements in the DOM.
The `ngIf` "conditional element" directive and the `ngFor` "repeater" directive are well-known examples.
Read more in the [Structural Directives](guide/!{docsLatest}/guide/structural-directives) page.
~~~
## Template
~~~ {.l-sub-section}
A chunk of HTML that Angular uses to render a [view](guide/glossary#view) with
the support and guidance of an Angular [directive](guide/glossary#directive),
most notably a [component](guide/glossary#component).
~~~
## Template-driven forms
~~~ {.l-sub-section}
A technique for building Angular forms using HTML forms and input elements in the view.
The alternate technique is [Reactive Forms](guide/glossary#reactive-forms).
When building template-driven forms:
- The "source of truth" is the template. The validation is defined using attributes on the individual input elements.
- [Two-way binding](guide/glossary#data-binding) with `ngModel` keeps the component model synchronized with the user's entry into the input elements.
- Behind the scenes, Angular creates a new control for each input element, provided you have set up a `name` attribute and two-way binding for each input.
- The associated Angular directives are all prefixed with `ng` such as `ngForm`, `ngModel`, and `ngModelGroup`.
Template-driven forms are convenient, quick, and simple. They are a good choice for many basic data-entry form scenarios.
Read about how to build template-driven forms
in the [Forms](guide/!{docsLatest}/guide/forms) page.
~~~
## Template expression
~~~ {.l-sub-section}
A !{_Lang}-like syntax that Angular evaluates within
a [data binding](guide/glossary#data-binding).
Read about how to write template expressions
in the [Template expressions](guide/!{docsLatest}/guide/template-syntax) section
of the [Template Syntax](guide/!{docsLatest}/guide/template-syntax) page.
~~~
## Transpile
~~~ {.l-sub-section}
The process of transforming code written in one form of JavaScript
(such as TypeScript) into another form of JavaScript (such as [ES5](guide/glossary#es5)).
~~~
## TypeScript
~~~ {.l-sub-section}
A version of JavaScript that supports most [ECMAScript 2015](guide/glossary#es2015)
language features such as [decorators](guide/glossary#decorator).
TypeScript is also notable for its optional typing system, which provides
compile-time type checking and strong tooling support (such as "intellisense,"
code completion, refactoring, and intelligent search). Many code editors
and IDEs support TypeScript either natively or with plugins.
TypeScript is the preferred language for Angular development, although
you can use other JavaScript dialects such as [ES5](guide/glossary#es5).
Read more about TypeScript at [typescriptlang.org](http://www.typescriptlang.org/).
~~~
{@a U}
## View
~~~ {.l-sub-section}
A portion of the screen that displays information and responds
to user actions such as clicks, mouse moves, and keystrokes.
Angular renders a view under the control of one or more [directives](guide/glossary#directive),
especially [component](guide/glossary#component) directives and their companion [templates](guide/glossary#template).
The component plays such a prominent role that it's often
convenient to refer to a component as a view.
Views often contain other views. Any view might be loaded and unloaded
dynamically as the user navigates through the application, typically
under the control of a [router](guide/glossary#router).
~~~
{@a W}
{@a X}
{@a Y}
## Zone
~~~ {.l-sub-section}
A mechanism for encapsulating and intercepting
a JavaScript application's asynchronous activity.
The browser DOM and JavaScript have a limited number
of asynchronous activities, such as DOM events (for example, clicks),
[promises](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise), and
[XHR](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest)
calls to remote servers.
Zones intercept all of these activities and give a "zone client" the opportunity
to take action before and after the async activity finishes.
Angular runs your application in a zone where it can respond to
asynchronous events by checking for data changes and updating
the information it displays via [data bindings](guide/glossary#data-binding).
Learn more about zones in this
[Brian Ford video](https://www.youtube.com/watch?v=3IqtmUscE_U).
~~~

View File

@ -0,0 +1,49 @@
@description
Angular applications are made up of _components_.
A _component_ is the combination of an HTML template and a component class that controls a portion of the screen. Here is an example of a component that displays a simple string:
<code-example path="quickstart/src/app/app.component.ts" linenums="false">
</code-example>
~~~ {.l-sub-section}
Try this **<live-example noDownload>QuickStart example on Plunker</live-example>** without installing anything.
Try it locally with the [***QuickStart seed***](guide/guide/setup)
and prepare for development of a real Angular application.
~~~
Every component begins with an `@Component` [!{_decorator}](guide/glossary)
<span if-docs="ts">function</span> that
<span if-docs="ts">takes a _metadata_ object. The metadata object</span> describes how the HTML template and component class work together.
The `selector` property tells Angular to display the component inside a custom `<my-app>` tag in the `index.html`.
<code-example path="quickstart/src/index.html" region="my-app" linenums="false">
</code-example>
The `template` property defines a message inside an `<h1>` header.
The message starts with "Hello" and ends with `{{name}}`,
which is an Angular [interpolation binding](guide/guide/displaying-data) expression.
At runtime, Angular replaces `{{name}}` with the value of the component's `name` property.
Interpolation binding is one of many Angular features you'll discover in this documentation.
~~~ {.l-sub-section}
### Next step
Start [**learning Angular**](guide/guide/learning-angular).
~~~