Deciding now, offers, promises, guesses and opinions.
I'll get it! / I think it will rain.
Plans made earlier. Things you can see coming.
I'm going to learn guitar. / Look out! It's going to fall.
Arrangements, often with a time.
We're flying to Vienna on Saturday.
Timetables and schedules.
The train leaves at 18:42.
Often more than one form works. The choice changes the emphasis, not whether it is correct.
This clears every star and point on this device. It can't be undone.