a song of ice and fire - What is the difference between a wight and an Other?

What is the difference between a wight and an Other in A Song of Ice and Fire?

At first I didn't think there was a difference, but there must be because Others can be "melted" by dragon glass and wights cannot.

Thoughts?

ETA: So, I've started re-reading the series, and I came across a passing, though interesting, mention of Others and wights in A Game of Thrones. Old Nan is telling Bran the story of the last hero and she says:

Old Nan nodded. "In that darkness, the Others came for the first time," she said as her needles went click click click. "They were cold things, dead things, that hated iron and fire and the touch of the sun, and every creature with hot blood in its veins. They swept over holdfasts and cities and kingdoms, felled heroes and armies by the score, riding their pale, dead horses and leading hosts of the slain." A Game of Thrones pg. 203 Kindle edition

I recalled that we were discussing whether wights and Others were working in concert with each other or merely two separate populations that happened to coexist in forests north of the Wall. From what Old Nan says, it would appear that the wights are, indeed, "soldiers" drafted into the Others' army.

I realize this in no way answers my initial question, and I still think that the accepted answer is the most thorough response to the actual question. This merely stands to confirm that wights and Others are definitely not the same creatures.

Answer

The Others are some sort of Ice demons, whereas wights are reanimated corpses. Not just human, but any corpse, as we have seen multiple times in the books, dead bears, horses, etc.

In the Prologue to A Game of Thrones you can read about both wights and Others. The Others are the one that surround Ser Waymar Royce, and watch him duel a single Other, and then ceremonially finish him off once he's fallen. You will notice they are described as sleek, intelligent and fast.

Conversely, when Will climbs down from the tree, he is killed by Ser Waymar Royce, who has now become a wight. Wights are in later books described as being rather like zombies: Gruesome, slow and clumsy, and not particularly intelligent.

(Note that in the TV-show, we see something completely different, but again we see both wights and Others)

I do not believe we know how wights are raised, or by whom exactly. I'm not entirely certain if we have ever seen them even work together (someone correct me with a specific example if I am wrong). It would be just like GRRM to show two different murderous types of beings and just by being vague allow us to believe they are allies.

For example:

• The Others who kill Ser Waymar Royce do not have any wights with them.


• The wight of Royce attacks Will on his own accord, no Others in sight.


• The attack on the Night's Watch force in The battle of The Fist of the First Men seemed to be made by a force of wights.


• When Sam kills the wight of Small Paul (with a glowing ember), he encounters a horde of wights outside. Again, only wights.


• When Sam kills the Other (with the dragonglass dagger), there are no wights around.

However, in the book, people do claim that wights are the servants of the Others.

Presumably, the theory is that the Great Other, some old, ancient evil has woken again after sleeping for thousands of years, sending out its captains -- the Others -- and resurrecting corpses as footsoldiers to create an army.

An interesting note is that it is hinted at that Craster is creating Others by sacrificing his newborn sons. I believe one of the old women at his compound tells Sam something like “They are coming. The sons.”, by which she ought not to mean wights, since infant-sized wights would hardly be a large threat.

Further hints to such an alliance of Craster's is that he is an outsider among the wildlings, he keeps himself separate from them, and Mance seems to know him for an enemy -- or at the very least, not a friend. Also noted when the Night's Watch take refuge at Craster's compound after the Battle of the Fist, Craster himself claims that he is "a godly man", that need not fear wights and Others. And indeed, they are not attacked by wights while staying there, even though they were hounded by wights the whole way there.