It's no big deal.

I have talked about a good deal before, it means that something was good value for money. You can see that lesson here. Today, we will look at the usage of deal in the expression:

a big deal

This is a situation, subject or event which people think is important. It is often used to highlight something as important.

Alice: Did you hear? Ted got the promotion!

Bill: Wow, that's a big deal isn't it?

Alice: Yeah, his salary will double and he'll have lots more responsibility.

Bill: Good for him! 

It can also be used to be modest and humble(謙辞 - けんじ). In this case, you will say "it's no big deal" or "it's not a big deal". 

A: I hear you got 100% on your test.

B: Yeah, it's no big deal.

A: Don't be so modest! You worked hard for that grade.

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C: Weren't you on TV for rescuing those kids?

D: It was not a big deal. I'm a firefighter, I was just doing my job.

Any questions?

Phil