The hairs on a cat grow from tiny pits in the skin called follicles. Primary hairs, also called guard hairs, are the longest ones in a cat's coat. These grow from individual follicles. These are the hairs that lie on top of the coat and may be either soft of bristly, depending on the breed. These hairs are found on most cats (with the exception of the 'hairless' variety).
Secondary hairs come in two types. Awn hairs are bristly tipped and about medium in length. Down hairs are fine, crinkled, and short in length. All secondary hairs grow in groups from single follicles, making them more likely to tangle and mat.
Grooming needs and shedding are primarily determined by coat type. Cats with a thick undercoats (which consist of secondary hairs) shed more and require more grooming. This is because secondary hair tend to mat and require more attention. So fluffy breeds with a soft undercoat such as the Persian, Himalayan, Balinese, or Birman will require more grooming. These cats have longer hair, but fluffy shorthaired cats shed just as much and need grooming as well.
Cats without the thick undercoat, including the Abyssinian, Siamese, and Oriental Shorthair, will still shed. You really can't avoid it. But they'll drop single hairs instead of large clumps of fuzz. These single hairs are easier to sweep off the couch and don't tend to embed themselves in carpets. These cats don't necessarily require regular grooming, but a quick brush once a week will at least cut down on those pesky hairballs.
Whatever cat you eventually choose, make sure you're aware of their grooming needs. You don't want a cat who's uncomfortable or unhealthy simply because you neglected to do your research.