Verbs simple aspect Continuous(progressive) aspect Perfect and Perfect Continuous aspect

Will is more formal than be going to and is therefore used more extensively in written English.

Present Simple as future
USE

• 
  We use the present simple to refer to the future in clauses of time and condition, e.g. after if, unless, when, as soon as, until, before, after, by the time:
  

We’ll phone you when we get there.
Please wait here until I get back.
And after everything, anything, whatever, It is important
Everything that you say will be recorded.
You will do whatever 1 ask you to.

• 
  We can use the present simple to refer to future events when the event is part of a fixed timetable, e.g. a travel timetable, a holiday itinerary, other organized events, an official trip by a member of the government. The event or the timing of the event is fixed by some official body, organization or timetable: