Most English native speakers will tell you that it is better to learn the proper form of words before using slang. This is to prevent english learners from making mistakes in their spelling, while also understanding proper word structure when they reach the writing level. I hope this was helpful.

I hear people use 'ain't' all the time, although I don't say it. However, I've never read 'hain't' nor have I heard anyone saying it.

Haint is a colloquial expression. 사투리같은 단어입니다

AIN'T is considered incorrect but is very common. It sounds uneducated. HAINT - most Americans will not even understand this word. I would only expect to find it in a novel about poor uneducated people in the 19th century. BTW - it can also mean GHOST.

I would not be surprised is a suspected burglar used the word "ain't." But no we'll educated person would. You should not use that word unless you are writing a story -- if you do, it will make a very bad impression on any educated person.