The full form of RAM is Random Access Memory. There are one or two RAM chips installed besides the CPU in the computer. RAM is used as a temporary memory storage. The information stored in it is volatile. It gets erased when the computer turns off. However, RAM provides speedy and easy access to the temporarily stored memory.
So, applications first load their necessary files on RAM, and access them rapidly when required. The memory gets erased when the application is not in use. It is also used by the operating system.