Commercial cat food comes in three different forms: dry, moist and canned.
Dry cat food comes in boxes or bags. Common flavours are beef, chicken, fish, tuna, salmon, poultry, heart, and liver. For some reason you never see pork flavoured cat food... or, for that matter, mouse flavoured cat food either. Dry food keeps well, although it does get stale when the bag or box is left open too long. It's also good for your cat because it helps to keep the cat's teeth clean. On the other hand, too much dry food can cause kidney problems, especially for neutered males, unless it's a special diet food.
Moist cat food usually comes in small enamel bags. It's available in several flavours, such as beef, fish, or chicken but, since it's less common than either dry or canned food, the variety in flavours is also less. Most cats do like it; but, since it's too moist to clean a cat's teeth and doesn't contain enough moisture to be really of much help to cats with kidney problems, it's not very useful. Moist cat food is perhaps best used as a supplement to your cat's diet.
Canned cat food varies greatly in quality. Some have chunks, or even whole recognisable pieces of fish and meat; other cans just contain a greyish mass that doesn't even remotely smell like meat or fish. It's available in any flavour that the dry food comes in, plus some others. Many cats like canned food better than dry food; but when fed only canned food, they can easily get teeth problems. Opened cans should be kept in the refrigerator to prevent un-scheduled biological experiments and the creation of new life forms.
The Right Food
Cats, on the whole, are picky. If you have a cat that gulps down everything you put in his food bowl, you should check the following two things:
Is the animal indeed a cat, and not an undercover dog posing as a cat?
Has it been more than a week since the cat has last seen food?
While there are always exceptions, a cat that is not picky about his food is a rather rare occurrence.
Once you find a brand, type, and flavour your cat likes, be careful not to buy too much. Another thing cats do well is change their mind. The food that was quite acceptable last week may not be acceptable today. Some cats like one brand and flavour, and will eat nothing else for years, others want variety. Sometimes a whole can or bag of one flavour is too much, a cat may eat the first bowl, leave most of the next, and happily have another bowl again a week or so later.
The cost or the brand name of the food makes little difference as to whether or not your cat will like the actual product... Neither do fancy TV commercials. We may be impressed by a beautiful, sleek cat leaping over a high fence; your cat most definitely is not. He either likes the way the food tastes, or he doesn't... and a TV commercial doesn't make any difference.
Tuna-flavoured cat food can cause some cats to be more picky about their food, refusing all other food that does not have the strong tuna flavour. This is called a 'tuna junkie'. Not all cats that are fed tuna will become addicted to the flavour, but some caution is advised.
Last of all, diet food can become necessary when a cat is too fat, or has specific problems with bladder or kidneys. It's very expensive, though there is no obvious reason why it should be more expensive to make; as with many things, you pay twice the normal price when it says 'diet' or 'health' on the bag. But it does have some special ingredients that do help the cat... so pay up if your cat needs it!