Unilever had an hand in this informative but very dry documentary about detergents. They are designed to clean in case you were wondering. Water? Well that's not so good at that - indeed, it isn't even very good at getting us wet! Yep - examples are provided to illustrate just how dry we are when we are soaked. Water molecules attract each other sideways and downwards. When it meets another substance then we get inter-facial tension - very useful for insects that lie atop the water waiting for their lunch. It's the detergent that allows these molecules to spread more readily - soaking a fabric ...