Symbols

Some of the most commonly used Internet slang is a combination of symbols, numbers and letters, I'm about to tell you about some of the symbol orientated slang. most people that use the Internet will understand the basic slang, but some more advanced stuff will confuse people. some basic symbol slang are :) smiley face, <3 love heart, ;) winky face, :P tongue face, :D big smile, :L laughing face, :@ angry face, :/ unsure face, :O surprised or offended face. :') happy crying face and :'( crying face.These are all used and understood symbols on sites such as facebook, twitter and tumblr. On the sites these symbols are recognised and sometimes made into actual pictures making it have a better appearance. While on other less advanced sites or less social run sites wont recognise and replace these symbols with pictures to represent them. So Its not worth using a lot of these symbol faces on unsocial sights as they may go unrecognised or confuse others, its best to use them on social sights a s they are recognised and understood.

http://www.djod.co.uk/2008/04/23/facebook-chat-emoticons-emotes-and-smilies/
In the link above is a more detailed explanation on how to create more faces, not all of those them work on socail sites.