The Orcs, a race in Azeroth (originally from Draenor) are a race of hulking muscular beasts, who's very culture is based on honor and conflict. Originally shamanic tribes, they were later corrupted by the Burning Legion (Basically the basic evil forces in every work of fiction), and became a race of masses of meat and rage.
The most prominent idea among WoW Orcs, is the idea of Lok'Tar Ogar, which means Victory or Death. In Orcish culture, you are strong, you are loyal, and you don't forfeit until someone dies. This honorable culture is the backbone of the Orcs, and everything they do is to uphold it.
The Orks of Warhammer fiction, are undoubtedly the silliest, yet most terrifying, presence in that realm of fiction. Basically, they are a race of cockney-accented, dull, and insane green men that outnumber and outbloodlust every single race in the galaxy. Their thirst for war is unquenchable and should they ever organize their whole race, may god have mercy.
Unsurprisably, the Orks are not natural. Created by an alien race known as the Old Ones, they were made for one purpose and one purpose only: To wage war. Because of this da orks are incredibly dumb, but incredible with warfare. On top of this, they have an innate psychic ability where if enough orks believe in something it will come true. For instance, the orks believe yellow makes things blow up better so when a rocket is painted yellow it will cause a bigger explosion than one painted blue of the same type. I don't ****** know its space magic I ain't gotta explain ****
I don't have a clever/insightful LotR thing to refernce them....
The Orcs of LotR mythos are essentially a race of twisted, beaten, abused elves. This race of neglected elves eventually became their own thing, and served the dark lord Sauron. They were a blackhearted race, disgusted with the living and violent. They came in two main variants: "normal" which was basically a small ugly man, and the Uruk, which were tall ugly men.
THE coolest ************* in LotR when I was a kid (and still are the coolest), Uruk-hai are just really big Orcs. With this increased size came increased brain capacity, and were a lot of times Saurons grunts he sent when a job needed to be done.
In general, Orcs are represented as monstrous brutes, with nothing more to them than warfare and rage. World of Warcraft gives them humanity, but in the end orcs are big brutes more than happy to crush anything in their way.
Sorry if this isn't top quality, a lot of the cool facts had to be omitted so it's not a 500 page essay for each. Drawing with poll to come within an hour or 2