the adjectives horror and terror are synonyms, meaning they both mean the same thing, with terror being higher than horror on the fear scale.
usually when refering to a movie that evokes terror the correct description would be horror movie not terror movie. there are different kinds of horror movies called subgenres, like splatter horror, slasher horror, torture horror...
splatter is often confused with slasher but slasher movies usually depict a psychopathic serial killer hunting and killing teens.
a splatter is a movie that focuses heavily on violence blood and gore. torture is self explanatory, like hostel, feardotcom...
so Friday the 13th is a splasher horror film.