These abbreviations work by themselves or as part of a longer sentence.
The symbol spread on early chat programs like AOL Instant Messenger in the 1990s.
I'm heading out to the party now.
Look at them sideways and you will see they are what is called "smileys" or "emoticons," as the last person who answered said, they represent different emotions.
However, he forgot to legally safeguard the sign and it quickly gained popularity.
Meaning: You want to bring the conversation to life.