Solution: A typical keyboard of a terminal (or a monitor that is directly connected to the computer) consists of about 100 keys in a way analogous to typewriter keyboard. The keyboards, as of 1990s, come in three different types:
a) PC keyboards. In addition to keys for typing letters and numbers, moving the cursor, and rolling the screen, these keyboards contain function keys that can be programmed to input a predetermined sequence of characters,
b)ASCII keyboards. These are simpler keyboards and may not have function keys or may have function keys that are preprogrammed.
c) ANSI keyboards. These keyboards do much the same thing as the ASCII keyboards, except that they must adhere to the ANSI standards for various control character and escape sequences (sequence of characters entered after an escape key) for changing the behavior of the terminal itself (e.g. reverse screen, blinking characters, etc).
The screen typically is 80 columns by 24 lines. There may be a 25th line for displaying terminal status information or current function keys when the function keys are programmable by software. The screen may be monochrome (actually green or amber) or color. With colored terminals, the screen colors can be set for background (the main 80-by-24 or 80-by-25 area), borders (the area surrounding the main area), and foreground (the characters typed).
First read the answer fully, then try to explain it in your own words. After that, open a few related questions and compare the concepts. This method helps you remember the topic for a longer time and improves exam preparation.