The game has crashed and I couldn't play

Put the summary of the bug you're having here
The game crashed
What I expected to happen was...:
Describe what you thought should happen here
I should be playing minecraft now
What actually happened was...:
Describe what happened here
I file report came and said the game crashed
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
3. ...