Read the articles too, but basically I can sum it up for you like this:
A wash is a very thin application of paint that is typically darker than the base coat it is being applied over. The idea behind a wash is that it will collect in the recesses of the model and create instant shading. It\'s a good idea to use something like dishwashing liquid (a very small amount) to break the surface tension of a wash so that you don\'t end up with \"tide marks\"
A Glaze is also a very thin application of paint that is used in a much more controlled manner to brighten or darken the base color it is being applied on. With a glaze, any pooling or collecting at all would be a bad thing as you shouldn\'t have that much paint on your brush. You basically want to wick off the vast majority of the paint in your brush on a towel so that when you paint a stroke, the beginning is about dry by the time you get to the end. You should not really be able to tell much of a difference with a single coat of a glaze. Glazes can be used to draw highlights and shades together or just give a lighter or darker hue to the surface you are coloring. Some people (myself included) use tons of glazes in lots and lots of coats to create highlights and shadows as it tends to give a very smooth transition when done correctly.
Hope that helps. The articles will cover it in more depth but that\'s a summary.