Colloquial- The spoken form a language. Language cannot be used while writing a formal text.
As I'm sure most people have noticed, spoken language and written language are usually very different.
Spoken language often involves slang—acronyms like 'lol', 'btw', 'hbu', etc. It might include shortened forms of words, nicknames for objects, or informal expressions.
Written language is often more formal. Even contractions are considered a colloquial language because words like 'can't' and 'won't' are often frowned upon in formal writing.
However, it is important to know that though spoken language is informal, it is not incorrect.
Until next time...
Stay Curious ;)