"Discs"Commonly referred to as optical discs, it is a round medium used to store digital information. The history of optical discs involves several types of discs, mainly including the following:
1.CD (Compact Disc): CD is one of the first types of optical discs, first commercially available in 1982. Originally used for audio storage, CD-ROM (Read-Only Memory) was later developed to store computer data. The CD has a diameter of 12 centimeters and can store about 700MB of data.
2.**Digital Versatile Disc): is the successor to the CD, first introduced in 1995. **Using more advanced technology on the same size disc, it provides greater storage capacity that can be used to store higher quality audio, **, and computer data. ** The diameter is also 12 cm, and a single layer can store 47GB, double layer up to 85gb。
3.Blu-ray Disc: Blu-ray is a high-definition optical disc format that was commercially available in 2006. It uses a blue-violet laser to read and write information, so it is able to store more data. Single-layer Blu-ray discs can store 25GB of data, and double-layer discs can store up to 50GB.
4.HD is a competitor to Blu-Ray and was commercially available in 2006. However, due to Blu-ray's larger storage capacity, Blu-ray eventually won the competition in the HD disc format, causing HD** to gradually withdraw from the market.
5.MiniDisc: MiniDisc is an optical disc format introduced by Sony Corporation in 1992 and is primarily used for audio storage. Although MiniDisc has achieved some success in the audio field, its market share has gradually decreased with the popularity of digital audio files.
These disc types play an important role in different application areas, from audio storage to HD** and computer data storage. With the development of digital technology, more and more data storage and transmission have shifted to cloud services and solid-state storage, and the use of optical discs has gradually decreased.
The precursors of discs can be traced back to traditional audio storage media such as records and tapes. Before digitization, people used a variety of analog technologies to record and ** sound. The following are the predecessors of the disc and related technologies:
1.Records: Before the advent of discs, records were one of the first commercial audio storages**. The most well-known is vinyl, which uses the technique of engraving, which records a sound signal by a groove in the surface of the record. This technique was very popular in the early to mid-20th century until the advent of digital audio technology.
2.Tape: Tape is a type of tape that uses magnetic tape to record audio and tape. Tape technology allows users to record and erase content, which makes it a convenient storage medium for reuse. Tape was widely used in recording studios, broadcasts, and home use until digital recording technology gradually replaced it.
3.Disks: Hard disks and floppy disks are media that use magnetically coated platters to store data. Hard disks played a key role in computer storage, while floppy disks were a common removable storage medium found in early personal computers. These magnetic discs also laid the foundation for later optical discs.
4.Optical disks: With the development of laser technology, optical disks have become a new type of digital storage**. The earliest optical disc was a CD (Compact Disc) for audio storage, and its technology was based on the principle of laser reading grooves. This laid the foundation for later high-capacity optical discs such as *** and Blu-ray.
These forms represent different periods of technological development, from engraving technology to magnetic technology to optical technology, each generation has brought higher storage capacity, better sound quality and more convenient experience.
The similarity between the appearance and usage methods of discs and records is mainly due to the fact that they are both circular mediums and usually have information recorded on one of the faces. Although they are similar in appearance and method of use, there are some significant differences in their development history and principles.
Similarities:1Round medium: Both discs and records are round mediums that are usually made of plastic or other materials. They are similar in diameter and both have a central hole.
2.Information Recording: Information on both discs and records is recorded by scribing or burning on the surface. Disc plates typically use a laser to carve tiny pits or bumps on the surface, while records use a die to carve spiral-shaped grooves on the surface.
3.**Equipment: Both discs and records require specific equipment to **. Discs typically require a laser reader or optical drive, while records require equipment such as a stylus or head to read the recorded information.
Differences:1Development History:
Records: The history of records dates back to the end of the 19th century, and the earliest records were made of glue, using a mechanical turntable and needle
Discs: Discs only appeared in the late 20th century, and the first disc was a CD (Compact Disc) jointly launched by Philips and Sony in 1982.
2.Principle: Record: The information of the record is recorded by carving a spiral groove on the surface, along which the stylus moves and vibrates, producing an audio signal.
Disc: The information of the disc is recorded by inscribed tiny pits or bumps on the surface, and the laser reader decodes the audio or data by reading the changes in these pits or bumps.
3.Storage capacity and quality:
Discs: Discs can store large amounts of audio or data with high quality and durability.
Records: Records have a low storage capacity and are susceptible to dust and scratches, are prone to damage, and have poor sound quality compared to discs.
While discs and records share similarities in terms of appearance and usage, there are significant differences in their history, how they work, and their storage capacity and quality.