That / Which

THAT‘  –  is used when you want to  ‘stress on the identity’ of the subject, or, when you want to add some specific detail – to help identify the subject, which is important for the meaning of the sentence.


This is the cab  that dropped me here yesterday.

These are the books  that  I bought from your store.

Books  that are written by business leaders, are usually quite expensive.

WHICH‘  –  is used when you just want to add some more information about the subject, which is not necessary for the identity of the subject.


For them, I am sending a pre-booked cab, which can also drop you home, if you want.

There are some interesting books, which I intend to buy soon.

Books, which are the best source of learning, are undervalued by youngsters today.