Swap space is a term used in computing to refer to the reserved area in a system's hard disk that acts as virtual memory when the physical memory is full. There are different synonyms that are used to refer to swap space, such as paging space, virtual memory, and swap file. Paging space is particularly used in IBM AIX operating systems where it refers to the virtual memory area. Virtual memory, on the other hand, is a general term used in computing to refer to the combination of RAM and hard disk space that enables a system to allocate more memory than its physical RAM. Finally, swap file refers to the actual file that contains the data swapped from the physical memory to the hard disk.