memorizer is an electronic device that uses semiconductors, memorizer media and other technologies to store data. Memory unit is actually a kind of sequential logic integrated circuit. They can be divided into read-only memory (ROM) and random access memory (RAM) according to the type of memory used. They have different functions and therefore different descriptions.

Semiconductor devices and magnetic materials are the main storage media for memory. The smallest unit of storage in a memory is a bistable semiconductor circuit or a CMOS transistor or magnetic material that stores a binary code. A storage unit consists of several storage units, and then a storage unit consists of many storage units.

The memory of a computer can be divided into memory and external memory. Memory stores are frequently used by computers during program execution and are directly accessible during an instruction cycle. External memory requires a computer to read information from an external storage device such as a tape or disk.

There are many types of memory. Random access memory (RAM) is used as a high-speed temporary memory during computation. Data can be stored, read, and replaced with new data in RAM. RAM is available when the computer is running. It contains information placed where the computer is dealing with the problem at the moment. Most RAM is "unstable", which means that information will be lost when the computer is shut down. Read-only memory (ROM) is stable. It is used to store the set of instructions a computer needs when necessary.

External memory is used to store images that are not acquired in real-time imaging tasks and has different levels of separation from computers. Images that have been diagnosed are usually stored for many years for legal purposes. These images are called "archives" (such as tapes), and they must be reinstalled on your computer to retrieve information.Images on hard drives are physically installed on your computer and can be accessed in milliseconds.