Orc (Middle-earth)

In Tolkien's writing, Orcs are described as humanoid, roughly human-sized, ugly and filthy. Although not dim-witted, they are portrayed as dull and miserable beings, who corrupt words (an insult, when stated by a philologist like Tolkien!) and are only able to destroy, not to create.
Orcs are used as soldiers by both the greater and lesser villains of The Lord of the Rings — Sauron and Saruman.
In Tolkien's Sindarin language, "Orc" is orch, plural yrch. In his late, post-Lord of the Rings writings (published in The Peoples of Middle-earth), he preferred the spelling "Ork", evidently mainly to avoid the form Orcish, which would be naturally pronounced with the c as /s/ instead of /k/. (In Tolkien's languages the letter c was always pronounced /k/.)It is also possible that the word is a Common Tongue Version of 'yrch', the Elvish word for Orc.

The origin of Orcs

The origin of Orcs is an open question. In Tolkien's writings, evil is not capable of independent creation, making it unlikely that the vala Melkor (later called Morgoth), who was obviously the first to produce them, could do that ex nihilo.
According to the oldest "theory" proposed by Tolkien, Orcs were transformed from Elves — the purest form of life on Arda (the Earth) — by means of torture and mutilation. Moreover, if Orcs were in fact Elves at their core, this could perhaps mean that they were also immortal — a fact which, if true, would seem inconsistent with Tolkien's treatment of Orcs, though the books do not openly confirm or deny it. If Orcs indeed were immortal, it holds no doubt that their fëar would not be allowed reincarnation by Mandos, if they even answered the calling. Most Orcs would probably fear the calling of Mandos, and therefore would see their fëar diminished to evil spirits. These may have been some of the evil spirits occasionally described in the books, such as the spirit which tempted Gorlim of Barahir's company, or the Barrow-wights. There is some evidence for the immortality, or otherwise long life of Orcs in The Return of the King: Gorbag and Shagrat, during the conversation which Sam overheard, mention the "Great Siege" of the Last Alliance. From the sentence it becomes clear they were there, and actually remembered it themselves: an event which lay millennia in the past.

There are hints in the History of Middle-earth series of books, (especially in Morgoth's Ring in the section "Myths Transformed"), that some Orc leaders, such as the First Age's Boldog, or the Great Goblin encountered by Bilbo and the Dwarves, may in fact have been fallen Maiar which had taken Orc form:

Some of these things may have been delusions and phantoms but some were no doubt shapes taken by the servants of Melkor, mocking and degrading the very forms of the children. For Melkor had in his service great numbers of Maiar, who had the power, as their Master, of taking visible and tangible shape in Arda. (Morgoth's Ring, "Myths transformed", text X')

Boldog (…) is a name that occurs many times in the tales of the War. But it is possible that Boldog was not a personal name, and either a title, or else the name of a kind of creature: the Orc-formed Maiar, only less formidable than the Balrogs (Author's footnote to the text X)

Melkor had corrupted many spirits - some great as Sauron, or less as Balrogs. The least could have been primitive Orcs. (Author's note to text)

Later under Morgoth's lieutenant, the necromancer Sauron, it has been suggested that Men were cross-bred with the Orcs. This process was later repeated during the War of the Ring, creating the fierce Orcs known as Uruk-hai.

Yet other Orcs may have begun as animals of vaguely humanoid shapes, empowered by the will of the Dark Lord (first Morgoth, later Sauron): this may explain the references to their "beaks and feathers" in Tolkien's writings.

The Orcs were beasts of humanized shape (…). ('Morgoth's Ring', "Myths transformed", text VIII')

It is certain all Orcs were dependent on the Dark Lord in various ways: after their leader was defeated, the Orcs were confused and dismayed, and easily scattered by their enemies. In the millennia after Morgoth's defeat and banishment from Arda, they were without a leader they degenerated to small, quarrelsome tribes hiding in the mountains. Only when Sauron returned to power did they begin to reclaim some of their old power. The same happened after Sauron's defeat by the Last Alliance of Elves and Men: only when Sauron returned as the Necromancer of Mirkwood did the Orcs become a real danger for Middle-Earth again.

While Tolkien originally saw all Orcs as descended from tortured Elves, later comments of his indicate, according to Christopher Tolkien in Morgoth's Ring ("Myths Transformed, text X"), that he began to feel uncomfortable with this theory. At about the same time he removed the references to the Thrall-Ñoldorin, he also began searching for a new origin for the Orcs. The Orc origin question may have been one of the problems Tolkien tried to solve by completely changing the cosmology and prehistory of Arda. By setting the origin of Men back to almost the same time as the Elves, he possibly allowed for Men to be the origin of Orcs all along. However, Tolkien died before he could complete this upheaval of the cosmology, and in the published version of Silmarillion, the Elf origin of Orcs was adopted.

It is interesting to note that to an extent, Tolkien did not regard Orcs as evil in their own right, but only as tools of Melkor and Sauron.
He wrote once that "we were all orcs in the Great War", indicating perhaps that an orc for him was not an inherent build-up of personality, but rather a state of mind bound upon destruction.

Orcs and goblins

In The Hobbit, Tolkien used the word "goblin" for Orcs, because he had not yet identified the world of The Hobbit with Middle-earth (which predated The Hobbit by several decades, in early writings which would later become The Silmarillion). Fortunately Tolkien did include some references to his mythology in the Hobbit, which later allowed him to identify the lands of the Hobbit with his Middle-earth.
In The Lord of the Rings, "Orc" is used predominantly, and "goblin" mostly in the Hobbits' speech.
This change can be seen either as a part of the shift towards the use of Elvish words that occurred during the period between the writing of The Hobbit and the writing of The Lord of the Rings, or a translation of the Hobbits' more colloquial manner (if we "accept" the books' authenticity and regard Tolkien merely as a translator). So essentially the race is correctly named "Orc", and "Goblin" is a colloquial "slang term" for Orcs used by Hobbits and sometimes picked up by Men and Elves. It is possible that "goblin" refers to the those of the orcish race who are not under the control of Sauron (or Morgoth), whereas using "orc" directly would refer to servants of (whichever) Dark Lord. Tolkien did mention several times that orcs were not inherently evil, something this theory would partly emphasize.

The original edition of the Hobbit and early drafts of the Lord of the Rings first used 'goblin' everywhere and used 'hobgoblin' for larger, more evil goblins: when goblins were replaced with Orcs Tolkien invented the term Uruk-hai for his more evil Orcs.

Individual orcs

Azog

He started the War of the Dwarves and Orcs in 2790 T.A. by killing Thrór, who came to revisit the ruins of Khazad-dûm.

In the following years he was the common enemy of all Dwarves, and the war he started climaxed in the Battle of Azanulbizar, where he killed Náin, but was himself slain by Náin's son Dáin.

His son Bolg inherited the rulership in Moria and continued it for another 150 years.

Boldog

Bolg

Bolg ruled Moria for some 150 years and led an army of orcs in the Battle of Five Armies. He was killed by Beorn.

Golfimbul

The Orc incursion in the northern Shire occurred during the reign of Arassuil as Chieftain of the Dúnedain, and the Orcs led by Golfimbul were but the most western pack of Orcs which had left the Hithaeglir. The only reason Golfimbul could make it all the way to the Shire was that the Rangers at the time were fighting many battles with Orcs, preventing them from settling all of Eriador.

Gorbag

In Peter Jackson's film version, Gorbag is an Orc, not an Uruk, and he is killed by Sam during Frodo's rescue.

Gorgol

Grishnákh

The name Count Grishnakh was also used as the stage name for Varg Vikernes (originally Kristian Vikernes) in the Norwegian black metal band Burzum. Vikernes is in prison for murdering Euronymous from black metal band Mayhem.

Lagduf

Lugdush

Lurtz

Lurtz is the first of Saruman's Uruks to be bred, and leads them into battle against Fellowship of the Ring at Amon Hen. In the book Boromir is slain by an unnamed orc or orcs; he is described as having been "pierced by many arrows". In the movie he is killed by Lurtz, who shoots him three times. Aragorn then intervenes, and after a brief fight stabs Lurtz and then cuts his head off. In the book Uglúk was the leader of the orc-band from the beginning.

The name "Lurtz" may have been derived by Jackson and his co-writers from the style of Tolkien's Orkish dialogue, but it also sounds similar to Lurch from The Addams Family.

Lurtz's name is never spoken aloud in the film, and is only known from the credits.

The character of Lurtz is one of the playable "heroes" in the computer game The Lord of the Rings: The Battle for Middle-earth.

Mauhúr

Muzgash

Shagrat

Ufthak

Uglúk

In Peter Jackson's movie adaptation of The Two Towers, Uglúk is played by Nathaniel Lees.

According to The Fellowship of the Ring movie, the initial leader of the orc-band was Lurtz (a character absent from the book), who was slain by Aragorn at Parth Galen.