It may not be just look more than a rainbow to most of us, but to the programmers this will make perfect sense.
Basically, sorting of numbers, strings etc. is used a lot in programming. The way this is done will vary by what algorithm you use.
Aldo Cortesi visualizes these sorting algorithms and has created a rainbow image of each of the algorithm used commonly in computer programming.
What is Sorting:
Sorting is way of arranging a number list such as: 4, 20, 6, 12, 100 in ascending/descending order or any other defined order.
Via:
Flowing Data