• Fragmentation is an unwelcome problem in the operating system in which processes are loaded and unloaded from memory, fragmenting available memory space. Because of their small size, processes cannot be allocated to memory blocks, and the memory blocks remain unused.
• It's also important to realise that as programmes are loaded and erased from memory, free space or a hole in the memory is created. These little blocks of memory can't be allocated to new processes, resulting in inefficient memory usage.
• The memory allocation system determines the fragmentation circumstances. These areas are split into little chunks of memory that cannot be allocated to arriving processes as the process is loaded and unloaded from memory. It's known as fragmentation.

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