What Does CD Mean
CD is a term that is part of the dictionary of the Royal Spanish Academy ( RAE ), which arises from the English acronym that refers to a compact disc (that is, a compact disc ).
A CD, therefore, is a digitally recorded optical element used for information storage . Music, videos, text documents and any other data can be stored on a CD.
For example: “When I was fifteen I asked my parents for a Michael Jackson CD” , “I can't find the operating system CD to install on the new computer” , “I'm going to make copies of the vacation photos on a CD ” .
The first known CDs were audio CDs , also known as CD-A ( CD Audio ) or as CDDA (for the expression compact disc digital audio ). Launched on the market in the early 1980s , for many years they were the main support for music distribution .
A CD-ROM , on the other hand, is a CD that stores all kinds of digital information. They are generally used on computers (computers), although they can also be read on DVD players, audio equipment, and other devices.
In the same way, we must not overlook the fact that there are other types of CD, among which we can highlight the following:
-CD-R, which is a recordable compact disc format. It has the particularity that it can be recorded in several sessions, but the information that is recorded can no longer be erased or overwritten. In the market they can be found with various capacities: 650 MiB, 700 MiB, 870 MiB and 900 MiB. It is considered that the first appeared in the year 1988 and it is established that they are recorded at a speed of 7,800 KB / s.
-CD-RW, which stands for rewritable compact disc. It has the particularity of being a CD that, unlike the previous type, can be re-recorded. That is, it can be recorded on many occasions as the data it has is erased. The origin of this CD was found in 1996, although it did not begin to be marketed until 1997. It is also interesting to know that it uses three different types of light: the reading laser, the writing laser and the eraser. It started out with a 650MB capacity, but is now available at 700MB.
It should be noted that the acronym CD can also refer to a board of directors , direct current , a sports club , a certificate of deposit and the direct complement .
Lastly, Cd is the symbol for cadmium (the chemical element whose atomic number is 48 ). Cd is a highly toxic heavy metal.
In the same way, cadmium or CD can be highlighted that it has a bluish-white color, that it is soft, that it is heavy and that it is used for many different applications. Thus it is used both as a pigment and also in the field of electroplating, in electronic accumulators or in photography.