What is the difference between the following sentences?
- Are you coming tonight?
- Will you come tonight?
"Are you coming tonight?" or "Are you going to come tonight?" both are questions that one asks when wanting to know whether the person is going to come over tonight. It is not a request like "Will you come tonight?" "Will you come tonight?" is what I would ask if I were inviting you to my house or to dinner or whatever tonight. "Are you coming tonight?" is not an invitation; it is a simple question. I don't know whether you're coming tonight; I'm not inviting you necessarily, but you may be swinging by to see me. In essence, the first one is a simple question regarding the future whereas the second one is a request, i.e. I'm inviting you. Here are two examples:
"Are you going to shut up now?" (I'm curious as to whether you are going to shut up.)
"Will you shut up now?" (I'm requesting that you shut up. I'm probably really angry with you. You are making a lot of noise and interrupting me.)