Dry food is most convenient because it does not spoil quickly, allowing the owner the freedom to be away from home for extended periods of time. Also, crunching dry food helps cats keep their teeth clean. Also, with dry food, make sure to keep out plenty of water. Low grade dry food may contain minerals that can cause urinary tract blockage, a serious health risk for cats.
Cats love it, and it is less likely to induce urinary More expensive.
Canned food is mostly water, and it doesn't stay fresh long, which is especially problematic for finicky eaters. Stays fresh longer than canned food. Often you are paying for the package, and the cute shape of the semi moist morsels.