Computer viruses cannot invade

It is impossible for computer viruses to invade ROM.

ROM is the abbreviation of Read-Only Memory. It is a memory that can only read out previously stored memory. Solid state semiconductor memory for data. (Recommended learning: PHP video tutorial)

means that the data stored in the ROM is usually written in advance before being loaded into the whole machine. During the working process of the whole machine, only Can be read but not written.

Its characteristic is that once the data is stored, it cannot be changed or deleted. Usually used in electronic or computer systems that do not need to change data frequently, and the data will not disappear when the power is turned off.

The data stored in ROM is stable and will not change after a power outage. Its structure is simple and easy to read, so it is often used to store various fixed programs and data.

Except for a few types of read-only memories (such as character generators) that can be used universally, the contents of the read-only memories required by different users are different. For ease of use and mass production, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM) and electrically erasable programmable read-only memory (EEPROM) have been further developed.

ROM

Read-Only Memory is a type of memory that can only read data. During the manufacturing process, data is burned into the circuit with a special mask. The data content cannot be changed after writing, so it is sometimes called "mask read-only memory" (mask). ROM).

The manufacturing cost of this memory is low. It is often used for startup in computers such as boot CDs. When the system is installed on the computer, the computer reads the operating system files in the C drive directory into the memory, and then Various accessories are called through the CPU to perform work. At this time, the system stores the memory as RAM. This type of CD is a COMPACT DISC laser disc, which is what CDs are like.

ROM-Read Only Memory read-only memory. Information is not lost after a power outage, such as the BIOS chip used for computer startup. The access speed is very low (compared to RAM) and cannot be rewritten. Since information cannot be rewritten and cannot be upgraded, it is now rarely used.

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