There are three important things that a good shaving cream will do for you.

1. Shaving cream softens your hair.
   
   Hair is actually pretty hard. When you shave, the collision between your hair and the razor blade gradually wears down the blade's sharp edge. Softening the hair (both by wetting it thoroughly before applying shaving cream, and by letting the shaving cream sit for a minute or two before shaving) will help increase the life of your razor blade.
   
   In addition, softer hair is more likely to cut evenly and cleanly. For people with coarse and curly hair, it's especially important for hair to be cut evenly; if the hair is cut at an angle, it becomes sharp, and if the hair curls in to the skin, it can penetrate the skin and cause razor bumps.



2. Shaving cream helps the hair stand up straight.
   
   The foamy, thick nature of good shaving cream helps to lift the hair, keeping it upright enough that it can be cut cleanly by the razor blade. Hair that is flat against your skin may not be cut evenly, or might conceivably be missed entirely.



3. Shaving cream provides lubrication.
   
   After all, you're dragging a sharp knife across your skin. It's a good idea to make sure that the blade can travel without too much resistance. This lubrication helps to reduce the irritation your skin would naturally feel as a result of being shaved.

There are a number of products that can provide all three of these benefits, and they're not limited to items traditionally labelled "shaving cream". But good, commercially available shaving creams are widely available and relatively inexpensive, so I tend to recommend them for most people in most circumstances.

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