Tak wrote the world, according to the dwarfs, but unlike most gods he does not require that the dwarfs think of him, merely that they do think. This makes him exceptional amongst Discworld gods who, without belief, would fade away to nothing more than small gods, eternally blown by the winds of mischance and always lamenting their loss of status and godhood.
There is a huge argument over what Tak actually wrote, to the point where there was almost a war amongst the dwarves. The ancient rendering of the text, held to be canon since time immemorial is:
The first thing Tak did, he wrote himself.
The second thing Tak did, he wrote the Laws.
The third thing Tak did, he wrote the World.
The fourth thing Tak did, he wrote a cave.
The fifth thing Tak did, he wrote a geode, an egg of stone.
And in the twilight of the mouth of the cave, the geode hatched, and the Brothers were born.
The first Brother walked toward the light, and stood under the open sky. Thus he became too tall. He was the first Man. He found no Laws and he was enlightened.
The second Brother walked toward the darkness, and stood under a roof of stone. Thus he achieved the correct height. He was the first Dwarf. He found the Laws Tak had written, and he was endarkened.
But some of the living spirit of Tak was trapped in broken stone egg, and it became the first Troll, wandering the world unbidden and unwanted, without soul or purpose, learning or understanding. fearful of light and darkness it shambles forever in twilight, knowing nothing, learning nothing, creating nothing, being nothing...
From 'Gd Tak `Gar' (The Things Tak Wrote), translated by Prof. W. W. W Wildblood, available from Unseen University Press for AM$8. In the original, the last paragraph of the quoted text appears to have been added by a much later hand.
This last addition, of course, is a negative description of a troll and has been ever used as one of the justifications (as if one were needed) to fight and kill trolls, as they are unwanted and unblessed by Tak.
However, there is a second possible translation, one that is unpopular and many dwarves wanted it declared heresy. At the time of the most notable battle of Koom Valley, the ancient dwarven Low King B'hrian Bloodaxe had come to meet Diamond, king of the trolls, to sign a peace-treaty, ending centuries of warfare between the two races, but they were betrayed on both sides by those who preferred the warfare, and the second translation was lost.
During the events of Thud!, Sir Samuel Vimes gets involved with the new Low King, Rhys Rhysson and together they hear the new translation, which is the same until the third part, where it changes considerably:
Then Tak looked upon the stone and it was trying to come alive, and Tak smiled, and wrote All things strive.
And for the service the stone had given, he fashioned it into the first Troll, and delighted in the life that came unbidden.
These are the things that Tak wrote!
This now makes it clear that Tak approved of trolls and looked on them as blessed just as much as dwarves. Suddenly we can see why it was considered heretical by hard-liners.
Rhys Rhysson and Mr. Shine, the new Diamond King of the trolls have used this to create a state of truce where many of the leaders of the most important dwarfish and trollish clans have come together to see whether a state of non-warfare between the two races can be achieved.
Compare this to the creation-myth of the Dwarves in Tolkien's Silmarillion. Here, right at the dawning of Middle-earth and before even the awakening of Elves, the Vala (angelic being) named Aulë, whose part in the making of Middle-earth had to do with shaping rock and mountain and placing metals and precious stones where the One God's creation would eventually find them, is pondering the place they have made. And how empty it is without intelligent life to appreciate and care for it. Thinking of the promise that one day, intelligent beings would arise in God's own time, he tries to jump the gun a bit, and makes the first Dwarves from the materials nearest to hand (stone, clay and metal). God, who sees all, got narked at this and manifested to berate Aulë for his presumption. He points out that only he can create such living beings - all Aulë, being a mere Archangelic Demiurge, has managed is to create hollow shells and the semblance of life, just puppets of his own making. Aulë offers to destroy his creation in penitence: but the Dwarves drop to their knees and beg him not to. Aulë realises in this instant that the Dwarves have ceased to be puppets, and are now fully alive and awake. For God has relented, and adopts Dwarves as a fully sentient part of his creation, but warns Aulë that "ever strife shall arise between thine and mine, the creatures of my own creation and the creatures of my adoption". In short, "You have been warned. These are going to be some right stroppy little buggers".
God then takes the first created Dwarves out of the care and sight of Aulë (who has ever after been reverenced by Dwarfs above all other Valar) and set them to sleep in seven different parts of Middle-earth, so as to awaken into life after the Elves and before Men.
Tak is one of the Polish words Himself has snuck in. Have you checked any More Polish?