Explain the concept of type erasure and its main purpose in programming.

Type erasure is a mechanism in Java used when working with generics. During compilation, information about the generic type parameters is removed (erased), and in the compiled bytecode, the types are replaced with their upper bound (usually Object).

The main purposes of type erasure:

• To ensure backward compatibility with code written before generics appeared.
• To allow the use of generics without changing the JVM.

Example:

List<String> list = new ArrayList<>();
// During compilation, this roughly becomes:
List list = new ArrayList();

Because of this, for example, it is not possible to create arrays of parameterized types or use instanceof directly with parameterized types.