An oriental pile rug consists of hundreds and possible thousands of loops of wool or silk individually tied by hand around warp and weft. This can be made of wool, cotton or even silk. This process if done on it's own would be similar to a sheet or blanket.
There are two main types of knots used by weavers in the carpet weaving process. The Turkish knot (called the Ghiordes) and the Persian knot (called the senneh). There was once a commonly held belief that the weavers of the Turkish origin universally used the Turkish knot while the Persians and the whole of east Asian used the Persian knot. However, there are many examples of which disprove this the generalisation. This has now caused the use of the term symmetrical and asymmetrical to describe the two different knots as it can no longer be used a universal way to determine origin of a rug. It does hold true that in Turkey, the Caucasus and West Persia the Turkish knot is the most commonly used knot, while in central Persia and the east all use mainly the Persian knot.
Some authorities assent that the neater appearance of the Turkish knot makes for a certain mechanical over-exactness and encourages the production of more angular, designs, whereas the irregularities in the Persian knot is the linchpin of the more exciting and vibrant designs. Typically this is what people think of as the glories of Persian carpet weaving. There is no doubt an element of truth is in this, but it is a sweeping generalization and one that is peppered with exceptions. For example, it would be difficult to find anything less mechanical in appearance that a Kurdish Kakaberu rug (Turkish knot) or anything mechanical than a Pakistan Bokhara (Persian knot).