1.2.3 Data units

Why must data be converted to a binary format?

• computers are comprised of many transistors which are tiny switches

• only have 2 states - on (1) and off (0)

• all data must be represented in this way to be processed

What are the units of data storage?

• bit - the smallest unit - a single 0 or 1

• nibble - 4 bits

• byte - 8 bits

• kilobyte - 1000 bytes

• megabyte - 1000 kilobytes

• gigabyte - 1000 megabytes

• terabyte - 1000 gigabytes

• petabyte - 1000 terabytes

How to calculate image file size?

colour depth x image height x image width

How to calculate text file size?

bits per character x number of characters

How to calculate sound file size?

sample rate x duration(s) x bit depth