What does CD-ROM mean?

CD-ROM refers to "read-only disc". The full name of CD-ROM is "Compact Disc Read-Only Memory", which is "Compact Disc Read-Only Memory", or "Read-Only Disc" for short. It is an external storage medium that can store a large amount of data; this kind of optical disc can only write data once. The information is permanently stored on the disc.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

CD-ROM (Compact Disc Read-Only Memory), CD-ROM, is a CD-ROM used on computers, an external storage medium that can store large amounts of data. This kind of optical disc can only write data once, the information will be permanently stored on the optical disc, and the information will be read out by the optical disc drive when used.

A compact disc is approximately 4.5 inches in diameter, 1/8 inch thick, and can hold approximately 660 megabytes of data. All CD-ROM discs are pressed from a master disc and then encased in a protective polycarbonate casing.

The data recorded on the master disk is in a spiral shape, spreading out from the center. There are many tiny pits on the surface of the disk, which are the recorded digital information. When reading data on a CD-ROM, a laser beam is used to scan the disc, and digital information is obtained based on the reflection changes of the laser on the small pits. The information on the disk is stored in spiral optical tracks.

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The speed of the CD-ROM drive is expressed as "X speed". The speed standards include 2x speed, 4x speed, 8x speed, etc., which are currently available. Reach 50 times speed. With the development of technology, digital versatile disks (DVDs) have appeared. Its storage capacity is larger, now reaching 9.4 gigabytes, and even higher, and the image clarity is better and the high-fidelity effect is also better.

CD-ROM is an optical disc specification used in computers. The device that reads the optical disc is called a CD-ROM drive. The data stored on the optical disc is read using laser light instead of Read magnetically, so discs can be stored for decades. The format of optical discs used by computers is the same as the format of music compact discs (CDs) played by laser discs in ordinary homes. The data capacity of an optical disc is as high as 650MB (74 minutes), which is about 450 1.44MB floppy disks. Generally, floppy disks are rewritable, but optical discs can only read data, not write data (if you have a CD-R recordable optical drive and a CD-R blank with burning software, you can write data on the optical disc. write data on-chip). At present, most computers have CD-ROM as standard equipment, and the speed of CD-ROM ranges from 1x, 2x...24x, 32x, to the fastest speed of 40x... Generations change very quickly, and the optical disc used in computer systems is also called CD-Title.

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