Used refers to a past practice or habit or state and is often used to indicate that something was done or existed in the past that is not done or does not exist at the present.
Examples of USED – Past time
I used to play guitar when I was younger.
I used to smoke cigarettes, now I am running.
Once we used to meet every Thursday night for a beer.
I used to thought that English is hard to learn.
There used to be a building here.
This is the park where I used to play with friends.