How does google get its pictures for the street view in google earth and maps?

ive always wanted to know how they took the pictures like that and put it into google earth or google maps. its been a wonder ive had for a long time|||they have this car thing that drives around and takes the pics. I actually saw it once so maybe I am in a pic somewhere, I dunno.|||The whole picture of world was taken by satellite.They may be in some parts but all are combined together.