The build is fairly flexible and performs extremely well against 1 base colossus. The idea behind it is that zealots with charge simply overwhelm the colossus and the archons (now massive units) plow through the force fields. Use high templars to make the archons due to their low mineral cost.
This build is by no means limited to just PvP. It is very successful vs terran bio armies as well.
Happy Sc2ing.