Units of information: bits, bytes and prefixes

Overview

Bits and bytes, the prefixes kilo, mega, giga and tera, why some count a kilobyte as 1,024 bytes, and conversions between units including how many photos fit on a card.

What you need to know

Answer each one before you reveal it.

Questions from this subtopic

Each one with the model answer underneath.

1. 1

   What is a bit?

   Model answer

   A bit is a single binary digit, either 0 or 1. A bit is the basic unit of information in a computer.

2. 2

   What is a byte?

   Model answer

   A byte is a group of 8 bits. One byte can hold 256 different patterns.

3. 3

   What do the symbols b and B stand for?

   Model answer

   A lower-case b stands for bit. A capital B stands for byte.

4. 4

   How many bytes are in one kilobyte?

   Model answer

   One kilobyte, written 1 kB, is 1,000 bytes. The prefix kilo means one thousand.

5. 5

   State the size of one megabyte in kilobytes and in bytes.

   Model answer

   One megabyte, written 1 MB, is 1,000 kilobytes. A megabyte is therefore 1,000,000 bytes.

6. 6

   How many megabytes make one gigabyte?

   Model answer

   One gigabyte, written 1 GB, is 1,000 megabytes. A gigabyte is therefore 1,000,000,000 bytes.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.