The close bracket represents a sideways smile )
Add in the colon and you have sideways eyes :
Put them together to make a smiley face

Use the dash - to add a nose

Change the colon to a semi-colon ; and you have a winking face

with a nose ;-)
Put a lower case o (halo) on top and now you have a winking, smiling angel 0

with a nose 0;-)
Use the letter 8 in place of the colon for sunglasses
Some chat and instant message programs automatically translate text smiley faces into graphics. In AOL Instant messenger (AIM), for example, if you type out the characters to make a "happy face" followed by "sad face" followed by "cool sunglasses" you would enter the following characters:
Once you've entered the text however, AIM converts the smiley text to graphics, if it can recognize the smiley pattern, and what you see on the screen will look like this:
Here are few examples of different smiley faces and their meanings:
Icon Meaning

Standard smile

With nose
:-E Buck-tooth
>-) Evil grin

Sad or frown smile
:-( Sad with nose
:-< Super sad
(((H))) Hugs
:-X Kiss on the lips
`

One eyebrow raised
:^) A broken nose
:-& tongue tied
E-

a Ham radio operator
Icon Meaning
:-# With braces
:'-) Happy Crying
{

Toupee smile

Winking smile
;-) Winking smile with nose
O

I'm an angel (boy)
O*-) I'm an angel (girl)
|-O Yawn

-D Gossip, blabbermouth
@>--;-- Rose
=^.^= Cat

Confused
C=

A chef
Icon Meaning
:-! "Foot in mouth"
:-D Laughter
:*) Drunk smile

Exclamation "What???"
:-@ Scream
:-0 Yell
%-( Confused
:-----) Long nose (Liar!)
:-.) Madonna
:-($) Put your money where your mouth is

I An egghead
|-O Yawning