Garbage collection (computer science)

When a computer program is run, it will use memory, to store certain values. While these values are used, there is a reference to them. When they are no longer used, there are no more references. Clearing the parts of memory which a computer program used, but where there are no more references is called garbage collection.

Garbage Collection (computer Science) Media

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  Stop-and-copy garbage collection in a Lisp architecture: Memory is divided into working and free memory; new objects are allocated in the former. When it is full (depicted), garbage collection is performed: All data structures still in use are located by pointer tracing and copied into consecutive locations in free memory.

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  After that, the working memory contents is discarded in favor of the compressed copy, and the role of working and free memory are exchanged (depicted).