These sorts of things always include a few pictures and biological descriptions so here we go:
In general, WOLVES are bigger, heavier bulkier animals with a broad head and rounded ears. An adult, male wolf can tip the scales around the150lb mark if he does not engage in an active lifestyle and his wife is a good cook.
COYOTES are smaller, have a more narrow, leaner head and face with pointed ears. They tend to buy large quantities of inferior grade merchandise from various industrial supply houses with ACME Company being a favorite. Coyotes are also more litigious than wolves and are much more likely to pursue lawsuits against parties they believe have wronged them. Wile E. Coyote, Plaintiff v. Acme Company, Defendant
Another helpful hint is you will be more scared, quicker when attacked by a pack of wolves versus a pack of coyotes. Screams during a wolf attack tend to be more of a muffled, gargling sound. More intelligible words such as "AHHHHH!!! Get it off of me!!!!!" can be more clearly heard from the victim during a run-in with coyotes.
A Man in the Woods