Memory allocation is a process by which the operating system provides programmers with blocks of memory. The programmer can request a certain number of bytes of memory from the operating system and use it for their program.

Memory allocation is an important part of programming, because it allows programmers to create and run programs that are much larger than what could be stored in a single computer's memory. Memory allocation is also important because it gives programmers more control over their program’s performance; they can tune how much memory they allocate to each part of their program to get the best results.

The main routines to handle memory allocations in c programming are:

• A malloc() is a function that allocates a block of memory. It does not initialize the allocated memory, and it is up to the programmer to ensure that the allocated memory is initialized properly.
• A calloc() is a function that allocates an array of space for an array of objects. It initializes each object in the allocated space to 0.
• A realloc() function changes the size of an existing block of memory, while keeping its contents intact. The old block must be freed before realloc can be used on it again, or else there will be a leak in your code.
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