Compact disc in the context of Blu-ray Disc

Sheet music is a handwritten or printed form of musical notation that uses musical symbols to indicate the pitches, rhythms, or chords of a song or instrumental musical piece. Like its analogs – printed books or pamphlets in English, Arabic, or other languages – the medium of sheet music typically is paper (or, in earlier centuries, papyrus or parchment). However, access to musical notation since the 1980s has included the presentation of scores on computer screens and the development of scorewriter computer programs that can notate a song or piece electronically, and, in some cases, "play back" the notated music using a synthesizer or virtual instruments.

The use of the term sheet is intended to differentiate written or printed forms of music from sound recordings (on vinyl record, cassette, CD), radio or TV broadcasts or recorded live performances, which may capture film or video footage of the performance as well as the audio component. In everyday use, sheet music (or simply music) can refer to the print publication of commercial sheet music in conjunction with the release of a new film, TV show, record album, or other unique or popular event which involves music. The first printed sheet music made with a printing press was made in 1473.

An optical disc is a flat, usually disc-shaped object that stores information in the form of physical variations on its surface that can be read with the aid of a beam of light. Optical discs can be reflective, where the light source and detector are on the same side of the disc, or transmissive, where light shines through the disc to be detected on the other side. They may contain analog or digital information, or a mixture of the two. Their main uses are the distribution of media and data, and long-term archival storage.
Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).

Sony Group Corporation, commonly referred to as Sony, is a Japanese multinational conglomerate headquartered at Sony City in Minato, Tokyo, Japan. The Sony Group encompasses various businesses, including electronics (Sony Corporation), imaging and sensing (Sony Semiconductor Solutions), film (Sony Pictures Entertainment), music (Sony Music Group and Sony Music Entertainment Japan), video games (Sony Interactive Entertainment), and others.

Sony was founded in 1946 as initially Tokyo Tsushin Kogyo K.K. by Masaru Ibuka and Akio Morita. In 1958, the company adopted the name Sony Corporation. Initially an electronics firm, it gained early recognition for products such as the TR-55 transistor radio and the CV-2000 home video tape recorder, contributing significantly to Japan's post-war economic recovery. After Ibuka's retirement in the 1970s, Morita served as chairman until 1994, overseeing Sony's rise as a global brand recognized for innovation in consumer electronics. Landmark products included the Trinitron color television, the Walkman portable audio player, and the co-development of the compact disc.

An audiobook (or a talking book) is a recording of a book or other work being read out loud. A reading of the complete text is described as "unabridged", while readings of shorter versions are abridgements.

Spoken audio has been available in schools and public libraries and to a lesser extent in music shops since the 1930s. Many spoken word albums were made prior to the age of cassettes, compact discs, and downloadable audio, often of poetry and plays rather than books. It was not until the 1980s that the medium began to attract book retailers, and then book retailers started displaying audiobooks on bookshelves rather than in separate displays.

Documentation is any communicable material that is used to describe, explain or instruct regarding some attributes of an object, system or procedure, such as its parts, assembly, installation, maintenance, and use. As a form of knowledge management and knowledge organization, documentation can be provided on paper, online, or on digital or analog media, such as audio tape or CDs. Examples are user guides, white papers, online help, and quick-reference guides. Paper or hard-copy documentation has become less common. Documentation is often distributed via websites, software products, and other online applications.

Documentation as a set of instructional materials shouldn't be confused with documentation science, the study of the recording and retrieval of information.

Disc and disk are both variants of the English word for objects of a generally thin and cylindrical geometry. The differences in spelling correspond both with regional differences and with different senses of the word. For example, in the case of flat, rotational data storage media the convention is that the spelling disk is used for magnetic storage (e.g., hard disks) while disc is used for optical storage (e.g., compact discs, better known as CDs). When there is no clear convention, the spelling disk is more popular in American English, while the spelling disc is more popular in British English.

DVD (digital video disc or digital versatile disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kind of digital data and has been widely used to store video programs (watched using DVD players), software and other computer files. DVDs offer significantly higher storage capacity than compact discs (CD) while having the same dimensions. A standard single-layer DVD can store up to 4.7 GB of data, a dual-layer DVD up to 8.5 GB. Dual-layer, double-sided DVDs can store up to a maximum of 17.08 GB.

Prerecorded DVDs are mass-produced using molding machines that physically stamp data onto the DVD. Such discs are a form of DVD-ROM because data can only be read and not written or erased. Blank recordable DVD discs (DVD-R and DVD+R) can be recorded once using a DVD recorder and then function as a DVD-ROM. Rewritable DVDs (DVD-RW, DVD+RW, and DVD-RAM) can be recorded and erased many times.

Blu-ray (Blu-ray Disc or BD) is a digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in 2005 and released worldwide on June 20, 2006, capable of storing several hours of high-definition video (HDTV 720p and 1080p). The main application of Blu-ray is as a medium for video material such as feature films and for the physical distribution of video games for the PlayStation 3, PlayStation 4, PlayStation 5, Xbox One, and Xbox Series X. The name refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs, resulting in an increased capacity.

The polycarbonate disc is 12 centimetres (4+3⁄4 inches) in diameter and 1.2 millimetres (1⁄16 inch) thick, the same size as DVDs and CDs. Conventional (or "pre-BDXL") Blu-ray discs contain 25 GB per layer, with dual-layer discs (50 GB) being the industry standard for feature-length video discs. Triple-layer discs (100 GB) and quadruple-layer discs (128 GB) are available for BDXL re-writer drives.

An album is a collection of audio recordings (e.g., music) issued on a medium such as compact disc (CD), vinyl (record), audio tape (like 8-track or cassette), or digital. Albums of recorded sound were developed in the early 20th century as individual 78 rpm records (78s) collected in a bound book resembling a photo album; this format evolved after 1948 into single vinyl long-playing (LP) records played at 33+1⁄3 rpm.

The album was the dominant form of recorded music expression and consumption from the mid-1960s to the early 21st century, a period known as the album era. Vinyl LPs are still issued, though album sales in the 21st-century have mostly focused on CD and MP3 formats. The 8-track tape was the first tape format widely used alongside vinyl from 1965 until being phased out by 1983, being gradually supplanted by the cassette tape throughout the 1970s and early 1980s; the popularity of the cassette reached its peak during the late 1980s before sharply declining during the 1990s. The cassette had largely disappeared by the first decade of the 2000s.

The album era (sometimes, album-rock era) was a period in popular music, usually defined as the mid-1960s through the middle of the 2000s decade, in which the album—a collection of songs issued on physical media—was the dominant form of recorded music expression and consumption. It was driven primarily by three storage formats: the 33⅓ rpm long-playing record (LP), the cassette tape, and the compact disc (CD). Rock musicians from the United States and the United Kingdom were often at the forefront of the era. The term "album era" is also used to refer to the marketing and aesthetic period surrounding a recording artist's release of an album.

Long-playing record albums, first released in 1948, offered the ability to sell larger amounts of music than singles. The album era arrived in earnest in the mid-1960s, when the Beatles began to release artistically ambitious and top-selling LPs. The industry embraced albums to immense success, and burgeoning rock criticism validated their cultural value. By the 1970s, the LP had emerged as a fundamental artistic unit and a widely popular item with young people. Some were concept albums, especially by progressive musicians in rock and soul.

A disc jockey, more commonly abbreviated as DJ, is a person who plays recorded music for an audience. Types of DJs include radio DJs (who host programs on music radio stations), club DJs (who work at nightclubs or music festivals), mobile DJs (who are hired to work at public and private events such as weddings, parties, or festivals), and turntablists (who use record players, usually turntables, to manipulate sounds on phonograph records). Originally, the "disc" in "disc jockey" referred to shellac and later vinyl records, but nowadays DJ is used as an all-encompassing term to also describe persons who mix music from other recording media such as cassettes, CDs or digital audio files on a CDJ, controller, or even a laptop. DJs may adopt the title "DJ" in front of their real names, adopted pseudonyms, or stage names.

DJs commonly use audio equipment that can play at least two sources of recorded music simultaneously. This enables them to blend tracks together to create transitions between recordings and develop unique mixes of songs. This can involve aligning the beats of the music sources so their rhythms and tempos do not clash when played together and enable a smooth transition from one song to another. DJs often use specialized DJ mixers, small audio mixers with crossfader and cue functions to blend or transition from one song to another. Mixers are also used to pre-listen to sources of recorded music in headphones and adjust upcoming tracks to mix with currently playing music. DJ software can be used with a DJ controller device to mix audio files on a computer instead of a console mixer. DJs may also use a microphone to speak to the audience; effects units such as reverb to create sound effects and electronic musical instruments such as drum machines and synthesizers.

CD-R (Compact disc-recordable) is a digital optical disc storage format. A CD-R disc is a compact disc that can only be written once and read arbitrarily many times.

CD-R discs (CD-Rs) are readable by most CD readers manufactured prior to the introduction of CD-R, unlike CD-RW discs.

In computing, an optical disc drive (ODD) is a disc drive that uses laser light or electromagnetic waves within or near the visible light spectrum as part of the process of reading or writing data to or from optical discs. Some drives can only read from certain discs, while other drives can both read and record. Those drives are called burners or writers since they physically burn the data onto the discs. Compact discs, DVDs, and Blu-ray discs are common types of optical media which can be read and recorded by such drives.

Although most laptop manufacturers no longer have optical drives bundled with their products, external drives are still available for purchase separately.

Semiconductor memory is a digital electronic semiconductor device used for digital data storage, such as computer memory. It typically refers to devices in which data is stored within metal–oxide–semiconductor (MOS) memory cells on a silicon integrated circuit memory chip. There are numerous different types using different semiconductor technologies. The two main types of random-access memory (RAM) are static RAM (SRAM), which uses several transistors per memory cell, and dynamic RAM (DRAM), which uses a transistor and a MOS capacitor per cell. Non-volatile memory (such as EPROM, EEPROM and flash memory) uses floating-gate memory cells, which consist of a single floating-gate transistor per cell.

Most types of semiconductor memory have the property of random access, which means that it takes the same amount of time to access any memory location, so data can be efficiently accessed in any random order. This contrasts with data storage media such as CDs which read and write data consecutively and therefore the data can only be accessed in the same sequence it was written. Semiconductor memory also has much faster access times than other types of data storage; a byte of data can be written to or read from semiconductor memory within a few nanoseconds, while access time for rotating storage such as hard disks is in the range of milliseconds. For these reasons it is used for primary storage, to hold the program and data the computer is currently working on, among other uses.

A CD-ROM (/ˌsiːdiːˈrɒm/, compact disc read-only memory) is a type of read-only memory consisting of a pre-pressed optical compact disc that contains data computers can read, but not write or erase. Some CDs, called enhanced CDs, hold both computer data and audio with the latter capable of being played on a CD player, while data (such as software or digital video) is only usable on a computer (such as ISO 9660 format PC CD-ROMs).

During the 1990s and early 2000s, CD-ROMs were popularly used to distribute software and data for computers and fifth generation video game consoles. DVDs as well as downloading started to replace CD-ROMs in these roles starting in the early 2000s, and the use of CD-ROMs for commercial software is now rare.

A record shop or record store is a retail outlet that sells recorded music. Per the name, in the late 19th century and the early 20th century, record shops only sold gramophone records. But over the course of the 20th century, record shops sold the new formats that were developed, such as eight track tapes, compact cassettes and compact discs (CDs). Today, in the 21st century, record stores mainly sell CDs, vinyl records and, in some cases, DVDs of movies, TV shows, cartoons and concerts. Some record stores also sell music-related items such as posters of bands or singers, related clothing items and even merchandise such as bags and coffee mugs.

Even when CDs became popular during the 1990s, people in English-speaking countries still continued using the term "record shop" to describe a shop selling sound recordings. With the vinyl revival of the 21st century, often generating more income than CDs, the name is again accurate.