A knot is prime if it is not equivalent to the unknot and is not equivalent to the Knot sum of two nontrivial knots.

The knot table is a list of all prime knots, with mirrors and reverses omitted. The list is arranged according to crossing number : the smallest number of crossings appearing in a diagram of the knot. Knots are given names such as 3 1 (the trefoil), 4 1 (the figure-eight) or 10 93 . In the latter case 10 is the crossing number of the knot, while 93 is the position of that knot in a certain conventional ordering. The knot table up to seven crossings is shown in Figure 1. The Knot atlas gives the knot table up to and including 10 crossings

Figure 1