What is Demand Paging?

In operating system, demand paging (instead of expectant paging) is a technique for Virtual Memory Management. In a framework that utilize demand paging, the OS duplicates a disk page into physical memory just if an endeavor is made to access it and that page is not as of now in memory. It takes after that a procedure starts execution with none of its pages in physical memory, and many page fault will happen until the greater part of a procedure’s working set of pages is situated in physical memory. This is a case of a lazy stacking method.