We form the standard passive with be + -ed form. We form the get passive with get + -ed form:
The trees in the garden were damaged in the wind. (standard passive)
The trees in the garden got damaged in the wind. (get passive)
We use the get passive especially in informal speaking. When we use the get passive, we also place a little more emphasis on the nature of the action itself or on the person involved in the action:
There were blizzards over night and the whole town got snowed in. (‘Get snowed in’ here means to be unable to leave the town because of heavy falls of snow.)
I’ve got good news for you. Jim finally got promoted.
They had only known each other for six months when they got married in Las Vegas.
The get passive is commonly used in speaking of events that are negative or not desired:
They’ve worked there for three years but they still got sacked (lost their jobs).
He feels his paintings are always getting criticised.
Our car got stolen last night.
We sometimes use a reflexive pronoun with the get passive. This suggests the subject was at least partly responsible for the event or made it happen:
I got myself locked out the other day. I stupidly left my keys in the bedroom. (or I got locked out …)