How does automatic garbage collection work in Java and how does it operate?

Automatic Garbage Collection (GC) in Java is the process of automatically freeing memory occupied by objects that are no longer used by the program.

How it works:

• The JVM tracks all objects in memory and determines which ones are reachable (have references from active parts of the program).
• Objects with no references are considered garbage and are eligible for removal.
• The garbage collector periodically runs and frees memory occupied by such objects.

The main GC algorithms in Java include:

• Mark and Sweep: first, all reachable objects are marked, then unmarked objects are removed.
• Copying: memory is divided into regions, live objects are copied to a new region, and the old region is cleared.
• Generational collection: objects are divided into generations (young, old), which optimizes performance.

For developers, this means they do not need to manually manage memory, reducing errors related to memory leaks and resource release.