Modern computer operating systems have a feature called virtual memory that enables a machine to use more memory than it actually has.
A virtual memory system divides a program's memory into smaller units called pages that are kept on the hard drive or in the RAM of the computer.
The operating system moves the RAM pages that haven't been accessed in a while to the hard drive when a programmer wants to access memory that isn't already in RAM, freeing up RAM memory for newly loaded pages. This procedure is known as switching or paging.
As the virtual memory system may make it appear, this enables programmer to use more memory than the system's physical RAM.
Operating systems employ virtual memory as a tool to control memory allocation for active programmer. By combining RAM and hard disc storage, it enables an application to access more memory than is really available on the computer's RAM.
Memory is needed for programmers to store their code, data, and variables while they are executing. The intricacy of the software and the data it is processing determine how much memory is needed. When an application needs more memory than is physically accessible in RAM, the operating system sets aside some space on the hard disc to serve as virtual memory.