Pan-cooking techniques: what's the difference?

Roughly, pan-cooking techniques can be classified by the following two attributes:

1) type of liquid used in the pan; this can be something fatty (melted butter, oil), creamy (cream, milk, gravy/reduction), watery (water, citrus juices)

2) amount of liquid used: this can range from none, to a thin surface layer, to partial submersion of the food, to near-total submersion (any more than that and you're boiling it! :P)

Let's have a look at how the different techniques break down in these dimensions, starting with the most familiar:

Frying: OK everyone knows this one... it uses a fatty liquid and partially submerges the food to be cooked. If you totally submerge the food, that's "deep frying".

Sauteing: The next most commonly known technique, again using a fatty liquid but only with a thin surface layer; typically, one sautes only long enough to brown the surface of the food. This has the advantage of preserving most of the food's freshness, but still gives it some cooked flavor and heats it gently.

Braising: This technique uses a watery liquid, either as a thin surface layer or partially submerging the food. This is typically done after sauteing or browing the food, in order to slowly cook the food in its own flavors (some sources define braising as the overall process of first browning and then cooking in a layer of water). This is great for slowly infusing flavors into meat (you can add flavors into the liquid).

Poaching: Use a watery liquid and partially or totally submerge the food (usually the latter). This is perhaps most commonly known in the classic "eggs benedict" recipe, but it's actually useful in many other situations when you want a light taste without much carbony flavor.

Searing: The simplest of all... NO liquid :) This is commonly done very briefly, and can be used either to lightly toast carbohydrates, or to quickly brown the outer layer of raw meat... in either case, you get a nice flavor boost while maintaining the freshness and vitality of the raw food. I strongly recommend this with fresh sushi-grade tuna.