What are the differences between Colour Graphics Adapter and Video Graphics Array graphics adapters?

The Colour Graphics Adapter (CGA), originally also termed as the Colour/Graphics Adapter or IBM Colour/Graphics Monitor Adapter introduced into 1981 year was IBM's first colour graphics card and the first colour computer display standard for the IBM personal computer.

The standard IBM colour graphics adapter graphics card was equipped with 16 kilobytes of video memory and could be joined either to a NTSC-compatible monitor or TV via an RCA jack, or else to a dedicated 4-bit "RBGI" interface CRT monitor, like the IBM 5153 colour display.

The term VGA that is Video Graphics Array refers particularly to the display hardware first introduced along with the IBM PS/2 line of computers in 1987, but by its widespread adoption has also come to signify an analog computer display standard, the 15-pin D-sub-miniature video graphics array connector or the 640 × 480 resolution itself. When this resolution has been superseded in the personal computer market, this is becoming an accepted resolution on mobile devices.    

Video Graphics Array was officially superseded by IBM's XGA standard; however in reality this was superseded by numerous slightly various extensions to video graphics array made by clone manufacturers which came to be known collectively as "Super Video Graphics Array ".