visual display unit (or monitor) is a piece of electrical equipment.

1. A visual display unit (or monitor) is a piece of electrical equipment, usually separate from the computer case, which displays viewable images generated by a computer without producing a permanent record.
2. The monitor comprises the display device, circuitry, and an enclosure. The display device in modern monitors is typically a thin film transistor liquid crystal display (TFT-LCD) thin panel,
3. The size of an approximately rectangular display is usually given as the distance between two opposite screen corners, that is, the diagonal of the rectangle.
4. Phosphor burn-in is localized aging of the phosphor layer of a CRT screen where it has displayed a static image for long periods of time. This results in a faint permanent image on the screen, even when turned off.
5. The monitor comprises the display device, circuitry to generate a picture from electronic signals sent by the computer, and an enclosure or case.
6. Burn-in re-emerged as an issue with early plasma displays, which are more vulnerable to this than CRTs. Screen savers with moving images may be used with these to minimize localized burn. Periodic change of the color scheme in use also helps.
7. Early digital monitors are sometimes known as TTLs because the voltages on the red, green, and blue inputs are compatible with TTL logic chips. Later digital monitors support LVDS, or TMDS protocols.
8. Green and amber phosphors were used on most monochrome displays in the 1970s and 1980s. White was uncommon because it was more expensive to manufacture, although Apple used it on the Lisa and early Macintoshes.
9. Most modern computer displays can show the various colors of the RGB color space by changing red, green, and blue analog video signals in continuously variable intensities. These are almost exclusively progressive scan.
10. Multiple devices can be connected to the same monitor using a video switch. In the case of computers, this usually takes the form of a "Keyboard Video Mouse switch" (KVM) switch, which is designed to switch all of the user interface devices for a workstation between different computers at once.