What Is A Swap File?

Swap File is a file on the hard disk used to store information that is not currently being utilized by the RAM memory. It allows the operating system to use hard disk space in order to simulate extra RAM memory. So when RAM memory is almost full and before performance decreases, the system swaps a section of RAM with the hard disk drive to free up memory for other programs. The term "swap-file" can also be recognized as “page file”.

By using the swap-file, the computer has the ability to use more memory than what the RAM can physically hold. This is because there is enough disk space available in the computer. But if the hard disk drive is full, the swap-file could not do its job of swapping memory with the RAM and consequently, limiting the computer to maximize its performance.