
Fundamentals
Objectives
Φ
Describe ways in which information can be represented in digital
electronic form (3).
• Convert between decimal, binary, octal and hexadecimal data;
represent negative numbers in fixed length binary form; perform
simple arithmetic in binary (3.1).
• Explain how numeric, text, sound and graphics information may be
coded (3.2).
Number codes
Computers are machines which work with electric signals that we can
interpret in any way we want, but which we normally think of as numbers.
This comes about because the original uses for computers were as calcu-
lating machines, and it was convenient to have the signals representin ...