Artifical Languages is a rather broad heading that can include several different classes of languages. The basic thing makes them members of this catagory is that they were consciously made by someone(s) (humans, so far).
Those Made for Humans to Speak:
ProgrammingLanguages
Fictional Languages:
- (those that have only been written about, not actually spoken)
- NewSpeak?
- SindarinLanguage?
- KlingonLanguage?