I'd say language is any medium of conveying information. There are many types other than spoken languages; sign language, eye contact, computer language, gestures, smilies

, symbols, pictures, mathematics, and more. They may not all be complete but they all have meaning and are a way of conveying information. So, I would concider them types of language.
Yes, even the middle finger is a form of language.
Pheace? Is that read
feace?