Q.9 What are the main differences between VGA and CGA graphics adapters?

Ans:

Colour Graphics Adapter (CGA), initially also known as Colour/Graphics Adapter or IBM Colour/Graphics Monitor Adapter introduced in 1981, was IBM's first colour graphics card, and first colour computer display standard for IBM PC.

Standard IBM CGA graphics card was equipped with 16 kilobytes of video memory and could be connected either to a TV or NTSC-compatible monitor via an RCA jack or to a dedicated 4-bit ‘RBGI' interface CRT monitor for example IBM 5153 colour display.

The term Video Graphics Array (VGA) refers specifically to display hardware first introduced with IBM PS/2 line of computers in 1987 however through its widespread adoption has also come to mean either an analog computer display standard, 15-pin D-sub miniature VGA connector or 640×480 resolution itself. Though this resolution has been superseded in personal computer market, it's becoming a popular resolution on mobile devices. GA was officially superseded by IBM's XGA standard though in reality it was superseded by many slightly different extensions to VGA made by clone manufacturers which came to be known collectively as ‘Super VGA'.