The Units of CSS can be grouped into four catagories.

• Length Units
• Percentage Units
• Color Units
• URL's

Length Units

• em
• ex
• px
• pt
• pc

Relative Length Units

Relative Units are used when you want your pages to scale evenly across a range of output devices.

em- The height of the elements font

letter-spacing: 0.1em

ex- The height of the letter "x" in the element's font

margin: 1ex

px- Pixels

font-size: 12px

Absolute Link Units

These units are called, "real world" units. These are best used for print work, or other occasions when the type of output device is known.

pt-Points

font-size: 14pt

pc-Picas (1pc=12pt)

font-size: 2pc

Percentage Units

Percentage units are relative to other values. Most often the percentage value is relative to the element's font size.

It is formed by a + or -, followed by a number, and followed by a %. There is NO spacing!!!

Color Units

Color units are specified in CSS by keywords, or RGB codes.

Example:

body{color: blue; background-color:#FF3399}

body{color: blue; background-color:#FF3399}

URL's

A URL can be single quotes ('), or double quoted (")

Example of a URL:

http://www.google.com

Information found at www.elated.com/articles/css-units/