What is the difference between table wine and cooking wine?

Cooking wine refers to unpalatable grape or rice wines that are reformulated for use as a food ingredient. Cooking wines typically are treated with salt, which functions as a preservative, thereby delaying the wine's conversion to vinegar. As a result, the wine can be frequently opened and closed without degrading it. 
 
Cooking wines are not widely endorsed by professional chefs, as they believe salt degrades both the wine and the food that is made with. Most  chefs prefer an inexpensive but drinkable wine for cooking. Their argument: If you wouldn't drink it, why would you add it to food?
 
Source(s):
What'scookinginamerica.net "Cooking with Wine--Wine in Cooking"