1. Hard disk: computer accessories used to store data. It is a non-volatile memory. The C drive, D drive, and E drive in the computer usually refer to the hard disk.
So even if you turn off the phone, the data inside will not be lost. Its appearance is a square box with a disc (like an optical disc) and a magnetic head for reading and writing the disc.
2. Memory: Due to the slow speed of the hard disk, if the CPU runs the program, all data will be read and written directly from the hard disk. Will greatly affect efficiency. So CPU will transfer the data used when running the software from the hard disk to the fast memory at a time, and then the CPU will exchange data with the memory. The internal storage is a volatile memory. As long as you power off the The data is gone. The memory itself is an integrated circuit board with several chips used to store data. Since this circuit board is generally made into a long strip, it is called a “memory bar”. The mainstream memory sticks now have a capacity of 2GB or 4GB.
3. The hard disk cache is the one on the hard disk’s circuit board. A small independent chip (just like memory). The hard disk cache, as its name implies, serves as a buffer for reading and writing hard disks. For example, if the CPU wants to write a large number of fragmented files to the hard disk, the CPU can first throw this bunch of files into the faster cache, and then the CPU can do other things first. The hard disk then writes this bunch of fragmented small files from the cache to the hard disk surface. Hard disk cache helps to improve the performance of sudden read and write and random read and write of hard disk.
4. Virtual memory, also known as page file. The memory in the computer is limited. What should I do if all the space on the memory is used up? The system can open up an area on the hard disk and use the hard disk as memory. Although the speed is slow, it is better than nothing.
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