A computer is an electronic device that accepts data, processes it, and outputs the intended result. Although there are many different types of memory in a computer. The most basic distinction is between primary memory, also known as system memory, and secondary memory, often known as storage. The main distinction between primary and secondary memory is access speed. Primary memory is the Main memory, which consists of ROM and RAM which is positioned near the CPU on the computer motherboard, allowing the CPU to read data. It's used to store data that the CPU requires right away so that it doesn't have to wait for it to arrive. Secondary memory is typically housed in a separate storage device, such as a hard disc drive or solid-state drive (SSD) which is connected to the computer system either directly or through a network. Secondary memory has a lower cost per gigabyte, but read and write speeds are much slower. Therefore, C?B?A?D is the correct sequence of computer memories that are ranked from largest to smallest in terms of storage capacity. Additional Information Information is stored in computers as binary code, which is written as a series of 0s and 1s. Bistable is a physical device that may be in either of two stable states to represent 0 and 1 can store each bit. Capacitors and transistors, which act as tiny electrical switches, are now employed for temporary storage, and long-term storage is done via magnetic discs or tape, or plastic discs having pit patterns.