CSCI 120 Introduction to Computation Ports and I / O devices ( cont . ) ( draft

This is the most basic input device. The keyboard contains keys users press to enter data into a computer. Desktop computer keyboards typically have from 101 to 105 keys. Keyboards for smaller computers, such as laptops, contain fewer keys. All computer keyboards have a typing area that includes the letters of the alphabet, numbers, punctuation marks, and other basic keys. The keys originally were arranged to reduce the frequency of key jams on old mechanical typewriters. The first six letters on the top alphabetic line spell QWERTY, thus giving the name QWERTY keyboard. A DVORAK keyboard, by contrast, places frequently typed letters in the middle of the typing area. Despite the logical design of a DVORAK keyboard, all keyboards today are QWERTY. Many keyboards also have a numeric keypad on the right side of the keyboard, two CTRL keys, two ALT keys, a set of arrow and additional keys between the typing area and the numerical keypad, and twelve function keys (enhanced keyboard). The command associated with a function key may vary, depending on the program with which we are interacting.