Units

You should be able to…

  • Define the terms bit, nibble, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte
  • Understand that data needs to be converted into binary format to be processed by a Computer

This diagram below clearly shows you the relationship between the units of data you are expected to know about. Lets go on to look at these in a little more detail…

sizes

Bit, Nibble, Byte

A bit is the smallest unit of data that is represented on a computer and is shown as a single binary digit, either 0 or 1.  A Nibble is 4 bits and a Byte is 8 bits, or 2 Nibbles.

bnbTitle

Kilobyte

‘Kilo’ is the Greek word for ‘Thousand’.  A Kilobyte is commonly referred to as being 1000 bytes. however It is actually 1024 bytes. A Kilobyte would be enough to store 1024 characters: This is shown visually below. Remember that each character (A) takes up a byte of storage (01000001).

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly 50 characters long $%!&()

This sentence is exactly

The following image is 15 Kilobytes or 15,000 bytes.

imagesMBM2P84P

Megabyte

A Megabyte is 1,048,576 bytes or 1,024 Kilobytes. However, you can refer to it as 1,000,000 bytes. The prefix ‘Mega’ means one million. To put it into context a Megabyte (MB) could store the following:

  • 873 pages of plain text (1,200 characters per page)

Gigabyte

A Gigabyte is 1,073,741,824 bytes. 1,024 Megabytes, or 1,048,576 Kilobytes. You can refer to it as 1,000,000,000 bytes! To put this into context a Gigabyte is enough to store the following:

  • 894,784 pages of plaintext (1,200 characters)
  • 640 web pages (with 1.6MB average file size)
  • 341 digital pictures (with 3MB average file size)
  • 1 750 MB Film

Terabyte

A Terabyte is 1,099,511,627,776 bytes, 1,024 Gigabytes, or 1,048,576 Megabytes. You can refer to it as 1,000,000,000,000 bytes. This would be large enough to store the following:

  • 916,259,689 pages of plaintext (1,200 characters)
  • 655,360 web pages (with 1.6MB average file size)
  • 349,525 digital pictures (with 3MB average file size)
  • 262,144 MP3 audio files (with 4MB average file size)
  • 1,613 650MB CD’s
  • 233 4.38GB Films

Lesson Tasks

1-Unit-Size

2. True or False

3. Find the Mistakes

Knowledge Check