Simon explains: The Knot Atlas is a complete catalogue of all the possible knots and links and links with 3 or fewer components and 11 or fewer crossings. The number of crossings is the measure of how tight the knot or link is.
Simon making knots using pipe cleaners. the “Unknot”:
Figure 8 knot:
Cinquefoil (Mom helped a little with that one):
And finally the three-twist knot: