RAM is the main and primary memory of the system. It is a hardware device and a part of the central processing unit which allows information to be stored and retrieved on a computer. It is volatile memory. Volatile memory requires constant source of power to retain information. RAM keeps the data until you do not save your information and data permanently on ROM. It does not store any information or data permanently. When power is lost or turned off, RAM will lose the information and data stored on it.