You may have been told that adding a pinch of salt to a pot of boiling water helps it boil faster -- this couldn't be further from the truth. While salt water is beneficial to cooking pasta, it has nothing to do with the rate at which your water boils, and it takes more than a pinch to make any difference. Cooking pasta with salt water improves the texture of the noodles and gives them a flavor boost.
If your pasta comes out slimy or sticky, it's because you aren't using salt -- or not enough salt. When you salt the pasta water, it helps the pasta cook evenly, preventing it from developing this slimy surface texture. Add one to two tbsp. of sea salt to a large pot of water to help your pasta cook evenly. If you do not want to rely on measurements, follow the advice of cookbook author Jill Silverman Hough and add enough salt to make your water taste as salty as the ocean.
Don't rely just on sauces, meats or vegetables to flavor your pasta dish -- salting the water gives flavor to the pasta itself. When pasta cooks, it absorbs water and swells. This means that when you cook with salt water, it absorbs the salt as well, seasoning itself from the inside out. Unlike other foods such as potatoes, though, pasta only absorbs so much, minimizing the risk of an overly salty flavor. While the salt does add flavor, it is not overpowering.
A relatively common cooking myth is that adding salt to water makes it boil faster, but this is not true. In fact, it has no bearing whatsoever on why you should use salt water to cook pasta. Adding salt to water before it comes to a boil actually increases the amount of time it takes to reach the boiling point, so wait until the water is already boiling to add the salt. When you eventually do add it, it only increases the water's temperature by about one degree Fahrenheit.
Though it seems to take longer, use a generous amount of water when boiling pasta. Small pots that are just big enough don't give your pasta room to mix around, and it actually takes longer to return to a boil after adding the dry noodles. Using a big pot returns the water to boil faster. Fill the pot with cold water -- according to the Environmental Protection Agency, cold contains fewer impurities than hot -- and cover it as you wait for it to boil in order to hold in the heat.