Challenge sites seem to be everywhere these days, and a lot of content is basically the same. In this handbook I am going to give all the hints and tips on solving challenges that I can, which is to say that I am not going to solve levels from other peoples sites, but I am going to show you the techniques that I use to solve these problems. If you are just setting out then think of this as a crash course in challenge solving.
Many sites now classify problems into different areas, although all sites tend to be essentially the same. Below you can skip straight to the area that you are interested in, but it is wise to remember that everything can be crossed with everything else in these challenge problems. If you are completely new to most of these areas, or just in need of some fresh ideas then you might like to read through all of it :)
I dont intend to specifically give a summary of tools but I will mention many useful tools throughout these pages. I believe that you should experiment and you will find tools that you can use and like yourself, but I will give many examples of tools that I like and use.