--- layout: doc_page --- # Tasks Overview Tasks are run on middle managers and always operate on a single data source. Tasks are submitted using POST requests to the Overlord. Please see [Overlord Task API](../operations/api-reference.html#overlord-tasks) for API details. There are several different types of tasks. ## Segment Creation Tasks ### Hadoop Index Task See [batch ingestion](../ingestion/hadoop.html). ### Native Index Tasks Druid provides a native index task which doesn't need any dependencies on other systems. See [native index tasks](./native_tasks.html) for more details. ### Kafka Indexing Tasks Kafka Indexing tasks are automatically created by a Kafka Supervisor and are responsible for pulling data from Kafka streams. These tasks are not meant to be created/submitted directly by users. See [Kafka Indexing Service](../development/extensions-core/kafka-ingestion.html) for more details. ### Stream Push Tasks (Tranquility) Tranquility Server automatically creates "realtime" tasks that receive events over HTTP using an [EventReceiverFirehose](../ingestion/firehose.html#eventreceiverfirehose). These tasks are not meant to be created/submitted directly by users. See [Tranquility Stream Push](../ingestion/stream-push.html) for more info. ## Compaction Tasks Compaction tasks merge all segments of the given interval. Please see [Compaction](../ingestion/compaction.html) for details. ## Segment Merging Tasks
The documentation for the Append Task, Merge Task, and Same Interval Merge Task has been moved to Miscellaneous Tasks.
## Kill Task Kill tasks delete all information about a segment and removes it from deep storage. Please see [Deleting Data](../ingestion/delete-data.html) for details. ## Misc. Tasks Please see [Miscellaneous Tasks](../ingestion/misc-tasks.html). ## Task Locking and Priority Please see [Task Locking and Priority](../ingestion/locking-and-priority.html).