Info about Cds
CDs
CD is just a shortened term for compact disk. CDs are made for digital media formats. At first their purpose was only going to be audio recordings, put they soon evolved into storing different kinds of data as well. Music CDs appeared commercially in 1982. They are still the standard way the music is physically stored.
Standard CDs are 120 millimeters in diameter and they can hold 700 mega bytes of data. This is about eighty minutes of music. There are some Mini CDs that are from sixty to eighty millimeters in diameter. Sometimes CD singles of computer drivers are stored on this type of disc. It will hold about twenty minutes of music.
The technology that created the audio CD was improved and the CD-ROM was created. It was made to store data and could only be used once. It could not be rewritten. These CDs were used to hold pictures, computer programs, and drivers as well as music.
The CD-ROMs are still very popular to use with computers. Music CDs and CD-ROMs had sold about thirty billion copies by 2004. Before 2008, over 200,000,000,000 CDs were purchased. This included the sales from all over the world.
CD-ROMs and CD-Rs are still very popular media in the computer industry. CDs became what music collectors bought. Very quickly the old vinyl records and cassette tapes were replace. It was not very long until all home and car stereos had CD players. The cassette players started disappearing a few years later.
The CD evolved from the technology of the Laserdisc that was created by Sony. In September of 1976 Sony did a demonstration of the first CD featuring all digital audio. By September of 1978 they had invented a CD with one hundred fifty minutes of playing time. In 1979, Philips demonstrated their version of a digital optical and audio disk.
Later on that year Philips joined together with Sony to create a new audio disk for digital media. Their task force of engineers consisted of a team of eight people.
It was in Germany that the first CD that was made for testing. It featured the music of Stauss that was performed by the Berlin orchestra being conducted by Herber von Karajan. The BBC played the first demonstration that was available for the public when the new Bee Gee’s Living Eyes album came out in 1981.
The new plant started making CDs in August of 1982. It was near the place that the first record for the gramophone had been produced ninety-three years earlier. The Visitors by ABBA was the first project made in the new factory.
The CD was supposed to replace vinyl records for playing music instead of a medium for storing data. It has grown into other realms of technology and applications.
The CD player has now replaced the cassette tape player in vehicles and homes. People now burn audio CDs instead of recording tapes. Other new media for digital recording like Blu-ray and DVD have used the same technology as the CD with a few improvements.