What is a garbage collector and how does it work in Python?

Garbage Collector in Python is an automatic memory management mechanism that frees memory occupied by objects that are no longer used by the program.

Python uses several methods for this:

1. Reference counting — each object has a reference counter that increases when a new reference to the object is created and decreases when a reference is deleted. When the counter reaches zero, the object is immediately deleted.

2. Cycle detector — reference counting cannot free objects that reference each other (cycles). For such cases, Python runs an additional cycle detector that periodically searches for and deletes such cycles.

Thus, the garbage collector helps prevent memory leaks and relieves the programmer from manually managing memory.