Which of the following is NOT a primary storage device?
All of the above is NOT a primary storage device.
Primary storage, also known as main storage or memory, is the main area in a computer in which data is stored for quick access by the computer's processor. On today's smaller computers, especially personal computers and workstations, the term random access memory (RAM) - or just memory - is used instead of primary or main storage, and the hard disk, diskette, CD, and DVD collectively describe secondary storage or auxiliary storage.
In this case, primary storage typically refers to random access memory (RAM), while secondary storage refers to the computer's internal hard drive. RAM, commonly called "memory," is considered primary storage, since it stores data that is directly accessible by the computer's CPU.
Random Access Memory (RAM) and cache are both examples of a primary storage device. The image shows three different types of storage for computer data. Primary storage's key differences from the others are that it is directly accessible by the CPU, it is volatile, and it is non-removable.