Many people nowadays know that CD-ROM is an important application in their computer. Some use it to listen to an audio CD while working on computer. But most of them not really know what is exactly the CD-ROM is. CD-ROM or "Compact Disc Read Only Memory" is an excellent medium for Interactive Multimedia. A CD-ROM is physically identical to a Digital Audio Compact Disc used in a CD player, but the bits recorded on it are interpreted as computer data instead of music. Most computers come equipped with an internal CD-ROM drive. We need to purchase an external or internal CD-ROM and attach it directly to our computer in order to to use any CD-ROM disc. A CD-ROM can hold about 650 Megabytes of data, the equivalent of thousands of floppy discs. With that highest capacity, clients will get a presentation that is elaborate and  intuitive to their audiences needs. CD-ROMs are not damaged by magnetic fields or the x-rays airport scanners and are highly resilient. When a CD-ROM is used inside a computer, we called  it CD-ROM.  

A CD-ROM drive uses an optically read, plastic coated disc. The information is recorded on the surface of the small 'holes' aligned along a spiral from the center to the edge. The drive directs the laser beam along the spiral to read the disc. When the laser hits a hole, the laser is reflected in one way, when it hits smooth surface, it is reflected in another way. Therefore, it is easy to code bits and also information.