Using Blending Modes in a Practical Sense?

[Blade Borge]

I'm trying to teach myself about all the blending modes, but it all looks very confusing. Plus, I'm not really sure the practical uses of these modes, could someone shed some light on what you usually use each mode for?

[milksac]

The best way to understand the modes is to open up AE, import some images and start experimenting.

Here's an overview of some of the modes that may be helpful;
http://tinyurl.com/2mtwgl

[oneinfiniteloop]

Go pick up After Effect Studio Techniques by Mark Christiansen, he has some great visual examples of the different blending modes and explanations of what they do, in a real sense and a mathematical sense, which I found very helpful.