Goblin Jester

Nory Nibblenog is the royal court jester for the Goblin king. His festive look belies his training as a master assasin. Silly clothes and bright colors are designed to distract and keep his targets laughing, so they don't see the knife before it's too late.

Gremlins

Gremlins are supernatural creatures to whom mechanical malfunctions are attributed. During World War II air force pilots often blamed such technical difficulties on sabotage from the Gremlins. They were attributed a large number of disruptive abilities, such as the ability to siphon off fuel, cause instruments to give false readings, or raise and lower the runway by ten feet.

I imagine that modern gremlins have probably gone on to destroy and dismantle the wide variety of computers, video game systems, and other types of consumer electronics.

Hobgoblins

Hobgoblins originated in European folklore as household spirits (which probably evolved from a form of ancient ancestor worship,) and played a similar role to goblins, brownies, pixies, etc. They were generally not seen as "evil," but would play tricks if not given the proper respect.

In modern fantasy fiction, Hobgoblins are a larger, stronger, brutish form of goblin. They are usually a greenish color, have features of various animals (claws, pig noses, etc.) and are mostly beholden to some figure of greater evil.

BugBear

BugBears were original creatures in European myth, similar to Brownies, Nixies, Hobgoblins, and other forest creatures. BugBears were envisioned as large, hairy monsters that would abduct naughty children. In modern fantasy fiction, they have become a race of larger, stronger, deadlier Goblins, usually acting as the "boss" of a group of weaker troops, and beholden to a superior (evil) power.

Goblin

Goblins were originally household spirits in European Pagan belief. "Goblins" went by many different names - Hob, hobgoblin, brownie, nixie, tomte, etc. Generally, such "faire folk" were helpful around the house unelss offended, by which they would then perform pranks and mischief. Such a belief in household spirits may have evolved from ancient ancestor worship.

Modern fantasy fiction has recreated the Goblin into a small, pig-like, gruntish humaniod of limited intelligence. Generally they tend to swarm by the thousands, are the antithisis of Dwarves, and tend to fall under the command of beings more powerful than themselves (wizards, demons, etc.)