SECAM in the context of "NTSC"

Color television (American English) or colour television (British English) is a television transmission technology that also includes color information for the picture, so the video image can be displayed in color on the television set. It improves on the monochrome or black-and-white television technology, which displays the image in shades of gray (grayscale). Television broadcasting stations and networks in most parts of the world transitioned from black-and-white to color broadcasting between the 1960s and the 1980s. The invention of color television standards was an important part of the history and technology of television.

Transmission of color images using mechanical scanners had been conceived as early as the 1880s. A demonstration of mechanically scanned color television was given by John Logie Baird in 1928, but its limitations were apparent even then. Development of electronic scanning and display made a practical system possible. Monochrome transmission standards were developed prior to World War II, but civilian electronics development was frozen during much of the war. In August 1944, Baird gave the world's first demonstration of a practical fully electronic color television display. In the United States, competing color standards were developed, finally resulting in the NTSC color standard that was compatible with the prior monochrome system. Although the NTSC color standard was proclaimed in 1953, and limited programming soon became available, it was not until the early 1970s that color television in North America outsold black-and-white units. Color broadcasting in Europe did not standardize on the PAL or SECAM formats until the 1960s.

Phase Alternating Line (PAL) is a colour encoding system for analogue television. It was one of three major analogue colour television standards, the others being NTSC and SECAM. In most countries it was broadcast at 625 lines, 50 fields (25 frames) per second, and associated with CCIR analogue broadcast television systems B, D, G, H, I and K. The articles on analogue broadcast television systems further describe frame rates, image resolution, and audio modulation.

PAL video is composite video because luminance (luma, monochrome image) and chrominance (chroma, colour applied to the monochrome image) are transmitted together as one signal. A latter evolution of the standard, PALplus, added support for widescreen broadcasts with no loss of vertical image resolution, while retaining compatibility with existing sets. Almost all of the countries using PAL are currently in the process of conversion, or have already converted transmission standards to DVB, ISDB or DTMB. The PAL designation continues to be used in some non-broadcast contexts, especially regarding console video games where it is referring to the markets other than North America and Japan.

${\displaystyle B-Y}$ indicates a color difference signal between blue (B) and a luminance component, as part of a luminance (Y) and chrominance (C) color model. It has different meanings depending on the exact model used:

• U in YUV, a generic model used for analog and digital image formats
• Cb in YCbCr, used for digital images and video
• Pb in YPbPr, used in analog component video
• Db in YDbDr, used in analog SECAM

${\displaystyle R-Y}$ indicates a color difference signal between red (R) and a luminance component, as part of a luminance (Y) and chrominance (C) color model. It has different meanings depending on the exact model used:

• V in YUV, a generic model used for analog and digital image formats
• Cr in YCbCr, used for digital images and video
• Pr in YPbPr, used in analog component video
• Dr in YDbDr, used in analog SECAM

Broadcast television systems (or terrestrial television systems outside the US and Canada) are the encoding or formatting systems for the transmission and reception of terrestrial television signals.

Analog television systems were standardized by the International Telecommunication Union (ITU) in 1961, with each system designated by a letter (A-N) in combination with the color standard used (NTSC, PAL or SECAM) - for example PAL-B, NTSC-M, etc.). These analog systems for TV broadcasting dominated until the 2000s.

Amateur television (ATV) is the transmission of broadcast quality video and audio over the wide range of frequencies of radio waves allocated for radio amateur (ham) use. ATV is used for non-commercial experimentation, pleasure, and public service events. Ham TV stations were on the air in many cities before commercial television stations came on the air. Various transmission standards are used, these include the broadcast transmission standards of NTSC in North America and Japan, and PAL or SECAM elsewhere, utilizing the full refresh rates of those standards. ATV includes the study of building of such transmitters and receivers, and the study of radio propagation of signals travelling between transmitting and receiving stations.

ATV is an extension of amateur radio. It is also called ham TV or fast-scan TV (FSTV), as opposed to slow-scan television (SSTV).