During and while

Both during and while show parallel actions or events.

During is a preposition so it is followed by a noun, which often represents the action itself.

While is a conjunction so it is used at the start of a complete sentence (or part of a sentence).

During

• I fell asleep during the presentation.
• During the phone call it became clear to me that my boss was angry.
• I drank too much coffee during the meeting.

While

• I fell asleep while he was giving his presentation.
• While I was talking to my boss, it became clear to me that he was angry.
• My computer shut down while I was away from my desk.