Definite and indefinite articles

 

A/an and the: meaning

A/an and the are articles. They are a type of determiner and they go before a noun.

A/an before a noun shows that what is referred to is not already known to the speaker, listener, writer and/or reader (it is the indefinite article):

Do you have a car?

A:

Do you live in a house?

B:

No, actually, I live in an apartment.

The before a noun shows that what is referred to is already known to the speaker, listener, writer and/or reader (it is the definite article):

Where did we park the car? (The speaker and the listener know what car is being referred to.)

We had to paint the apartment before we sold it. (The speaker and the listener know what apartment is being referred to.)

The makes a noun specific.

Compare

Have you been to anice rink?	The speaker is not asking about any one specific ice rink but is asking whether they have been to any ice rink (an doesn’t refer to a specific ice rink)
Have you been to the ice rink?	The speaker and listener know the ice rink which is being referred to (e.g. the one in their town/the local one). The makes the noun ice rink specific.

Not specific	Specific (‘the one you and I know’)
Would you like an apple?	Would you like to try the apple pie?
Do you have a cat?	Have you seen the cat?