Use the adjective other to distinguish something as being different or distinct. You might ask your friend if she's coming to the movies with you, or if she has other plans.
If you don't get the first job you apply for, you'll have to see if other places are hiring. If you're sweating in the hot summer sunshine, you might want to cross to the other side of the street. Other can take various meanings, from "opposite" to "strange" to "additional." You might also notice other in phrases like "how the other half live," meaning rich versus poor people, or "the other day" — a few days ago.