Department of Computer Science
CS1102 Introduction to Computer Studies
Lecture 06
Computer System Hardware
Semester A, 2025-2026
Computer System
Computers are electronic devices that can follow instructions to accept input, process data, and produce information
Input
Input is any data or instructions entered into a computer
Input devices are hardware used to translate words, numbers, sounds, images, and gestures that people understand into a form. that the system unit can process
Keyboard
A keyboard converts numbers, letters, and special characters that people understand into electric signals
Keyboard Categories (1)
Traditional keyboards
• Full-size keyboards widely used on desktops and computers
• Standard US traditional keyboard has 101 keys including function keys, navigation keys, and a numeric pad
• Toggle keys such as Caps Lock key turn a feature on or off
• Combination keys such as Ctrl key perform. an action when held down in combination with another key
Keyboard Categories (2)
Laptop keyboards
• Attached to the laptop system unit and designed to fold up with laptop monitor
• High-end tablets may include a laptop keyboard that can be removed from the tablet or double as a protective case
• Come in a variety of configurations, depending on manufacturer and the size of the laptop
Differences between desktop keyboard vs. laptop keyboard
• Size
• Function keys
• Layout
• Connectivity
Keyboard Categories (3)
Virtual keyboards
• Primarily with cell phones and tablets
• Do not have physical keys that are present in other keyboards
• Keys are displayed on a screen and selected by touching their image on the screen
Differences between virtual vs. physical keyboard
• Form. (software vs. hardware)
• Tactile feedback
• Flexibility for customization