Blanching vegetables is a method used in both China and French cooking a lot.  Blanching locks in the flavor, color an mutritional value.  The origional meaning of the word "blanch" is to whiten and the method was indeed oigionally uset to whiten or clean vegetables brought in from the garden or field.  Today in culinary circles the term usually means to prepare vegetables by the following method:

Trim and cut vegetables to desired size and shape.  Bring a large pot of water to the boil.  Place the vegetables in the boiling water and leave for 1 to 3 minutes, depending on the type and size of each vegetable.  Remove from the boiling water and immediatelly put in cold or better yet, ice water to stop the cooking.  When thoroughly cooled, drain well.

Your vegetables are now ready to use in any of a number of applications.  Use as they are in salads.  Place in a marinade or vinaigrette and use as anti-pasta.  You may also use them as the Chinese do; blanch them and set them aside ready to toss into stir-fries or other dished.  Blanching before proceeding with some other cooking process is a good way to preserve flavor, color and nutritional quality and give your vegetables that extra fresh feel.