diff --git a/core-java/src/main/java/com/baeldung/interfaces/Box.java b/core-java-lang/src/main/java/com/baeldung/interfaces/Box.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/Box.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/Box.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/Employee.java b/core-java-lang/src/main/java/com/baeldung/interfaces/Employee.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/Employee.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/Employee.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/EmployeeSalaryComparator.java b/core-java-lang/src/main/java/com/baeldung/interfaces/EmployeeSalaryComparator.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/EmployeeSalaryComparator.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/EmployeeSalaryComparator.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/HasColor.java b/core-java-lang/src/main/java/com/baeldung/interfaces/HasColor.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/HasColor.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/HasColor.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Car.java b/core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Car.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Car.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Car.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Fly.java b/core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Fly.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Fly.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Fly.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Transform.java b/core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Transform.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Transform.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Transform.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Vehicle.java b/core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Vehicle.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/multiinheritance/Vehicle.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/multiinheritance/Vehicle.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/polymorphysim/Circle.java b/core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/Circle.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/polymorphysim/Circle.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/Circle.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/polymorphysim/MainTestClass.java b/core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/MainTestClass.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/polymorphysim/MainTestClass.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/MainTestClass.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/polymorphysim/Shape.java b/core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/Shape.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/polymorphysim/Shape.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/Shape.java
diff --git a/core-java/src/main/java/com/baeldung/interfaces/polymorphysim/Square.java b/core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/Square.java
similarity index 100%
rename from core-java/src/main/java/com/baeldung/interfaces/polymorphysim/Square.java
rename to core-java-lang/src/main/java/com/baeldung/interfaces/polymorphysim/Square.java