Watercolour pencils are different to standard colouring pencils in that they have a water soluble lead, meaning that the finished sketch or colouring can be brushed with water to transform it into a watercolour painting. The picture instantly becomes more vibrant, and the colours pop off the paper.
Using watercolour pencils allows for so much more precision and control than standard watercolour painting because you can layer your colours over each other, which blend together in the finished item.
