How Computers Work

Input: Information and programs are entered into the computer through Input devices such as the keyboard, disks, or through other computers via network connections or modems connected to the Internet. The input device also retrieves information off disks.
Output: Output Devices displays information on the screen (monitor) or the printer and sends information to other computers. They also display messages about what errors may have occurred and brings up message or dialog box asking for more information to be input. The output device also saves information on the disk for future use.
Processing: The CPU or central processing unit is sometimes called the Control Unit and directs the operation of the input and output devices. The Coprocessor or the Arithmetic-Logic Unit does arithmetic and comparisons. The memory or RAM temporarily stores information (files and programs) while you are using or working on them. The BIOS or basic input/output system controls the dialogue between the various devices.
Keyboard Layout and Data EntryENTER or RETURN - Moves the cursor down one line and to the left margin. Enter also process commands such as choosing an option in a dialog (message) boxes and submitting a form.
DEL or DELETE - Deletes the character at cursor and/or characters to the right of the cursor and all highlighted (or selected) text.
BKSP or BACKSPACE - Deletes the character to the left of cursor and all highlighted text.
SPACE BAR - Moves the cursor one space at a time to the right
SHIFT KEY - Use the shift keys to type capital letters and to type the upper character on keys with two characters on them
CAPS LOCK - Locks the keyboard so it types capital letters (a light goes on when caps lock is on)
TAB - Moves the cursor five spaces to the right (number of spaces are usually adjustable). Tab moves to the next field in a form or table (Shift-Tab for previous field).
ESC or ESCAPE - Cancels a menu or dialog box
ARROW KEYS - Moves the cursor around document without changing text
FUNCTION KEYS or F KEYS - Access commands by themselves or in combination with the three command keys; CTRL, SHIFT, and ALT