free

Lesson in the C Programming Roadmap · Stage 13: Structuring Codebase

Last updated 14 September 2026

What is free?

free is a standard library function used to deallocate a block of memory that was previously reserved on the heap. When you call this function, it releases the specified memory back to the system so that it can be used for other purposes in the program. Passing a pointer to the start of a previously allocated memory block to free effectively marks that space as available, though the pointer itself remains unchanged and should ideally be set to NULL immediately afterward to prevent accidental use of dangling references.

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Free resources to learn free

ArticleC Deallocate Memory
ArticleC library - free() function
VideoReleasing the Dynamically Allocated Memory using free()

free: common questions

Can I learn free in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain free in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this free tutorial for beginners?

It is lesson 71 of 141 in the free C Programming roadmap, in stage 13, Structuring Codebase. If you are new to C Programming, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.