What does BTW stand for? 

BTW stand for by the way. 

What is BTW mean? 

The full form of BTW is by the way which means you are adding something else, what actually you are saying.

BTW stands for? by the way 

Example of BTW?

An example of by the way is when you are talking with someone that I love you she said LOL then you replied by the way I'm serious I'm not kidding. This is the best example to understand what actually the world BTW.