How to say "We" in Chinese? 我们 or 咱们?

咱们 vs 我们

咱们 and 我们 both mean “we” or “us”, but they have difference.

  

咱们 usually includes all the people that you’re talking to. 
Yet 我们 sometimes includes, sometimes it doesn't.

Say for example:

If you meet a friend Mike who’s not your workmate.

You can say：Mike，我们公司是卖车的，你们公司是做什么？

You can’t say：Mike，咱们公司是卖车的，你们公司是做什么？(咱们includes Mike)

If Mike is your workmate.

Both are correct:

Mike, 我们公司明天放假吗？

Mike，咱们公司明天休息吗？