The biggest difference between most brand name drugs and generic versions is that the brand product costs significantly more.
Brand and generic drugs are therapeutically and chemically equivalent. Generic drugs are required to have the same active ingredient, strength, dosage form, and route of administration as the brand name product. Trademark laws in some countries require the drugs to look different, so the generic version may be a different color, a different shape, have a different taste, or contain inactive ingredients that are different.