Establishing shots

An Establishing shot is a shot used to tell the audience where or when the scene is taking place,

for example, If someone in a movie gets into a car crash in the next scene we would see a exterior (outside) shot of a Hospital then a few images of the patients and doctors within the hospital until we see our main character. The audience knows our hero is in the hospital because we got to see a hospital that's the Establishing shot. It sets up the scene.

Now it doesn't only have to be hospital building, an establishing shot can be a house, a city or even a person as long as the audience understands where the story is taking place in that particular scene. Every disaster movie  has a establishing shot.

"The Day After Tomorrow." 

We know this is New Work because of The Statue of Liberty, landmarks are a great for establishing shots.

Here are a few more examples of Establishing shots. 

Film is storytelling with images guiding the audience where the story takes them, and Establishing shots is one of the ways to tell that story smoothly.