Summarize:

Different breeds of cats have distinct characteristics, and it is important to do some research to determine the best breed to fit your lifestyle.  While less than 10% of cats are considered “purebred” to one specific breed, an understanding of the breeding groups in general will be very helpful even if you are adopting a common house cat:  Natural breeds:  These cats have long, thick coats developed in cold climates; heavy, square bodies; and are the most sedentary group of the three purebred groupings.  Common breeds within this group are American and British shorthairs, Persians, and Maine coon cats. Semi-foreign or Hybrids:  Considered an in-between group, these cats have slightly oval eyes; moderately wedge-shaped heads; and a leaner, more muscular body than the other breeds.  They have a moderate energy level in comparison, except for the Abyssinian breed, which is high energy.  Other common breeds within this group are the Russian blues and Ocicats. The Orientals:  These cats originated in warmer climates and so they have very little body fat, lighter coats, and very long legs, tails, ears, and bodies.  This group is the most active and talkative of the three purebred groupings.  Common breeds within this group are Siamese, Burmese, and Cornish rexes. It is important to consider the time you have available to train and play with your cat, as well as your expectations for its behavior.  If you work full time or have young children, it might be best to adopt an older cat since kittens and adolescents are a lot of work to train and watch over. If this is your first cat, try to avoid cats that are very demanding (of your attention, of their space, etc.) as it may be too big a challenge for a beginner. After doing some research to determine the best breeds for your lifestyle, it is important to realize that this is just a “best guess.” Be sure to go and interact with your cat in person a few times before making a decision.  Also, adoption counselors at shelters often have great advice to help you find a cat whose personality matches your own. It is very important that any cat you get feels safe and comfortable interacting with the other people and pets in your life already.  When visiting the shelter or breeder, be sure to bring your kids, partner, or anyone else that will have regular contact with the cat along with you.  If you have existing pets, talk to the breeder or the shelter counselors about the best way to introduce the pets to see if there are any potential issues. A breeder will have a better understanding of the cat’s history and tendencies, but an animal shelter or rescue group will only be able to hypothesize about a cat’s past illnesses and elaborate on its current state.  While no shelter would want to release a sick cat for adoption, it is still important to educate yourself about common signs of illness in cats so you can ask questions and make observations:  Changes in water intake (both drinking more and drinking less) can indicate that the cat has diabetes or kidney disease. Unexpected weight loss or weight gain despite normal eating habits can indicate diabetes or hyperthyroidism. Bad breath can mean tooth decay, dental disease, or a digestive disorder, while sweet or fruity-smelling breath can be a sign of diabetes. Pay attention to the cat’s grooming habits.  If a once well-groomed cat starts to appear unkempt, this is a sure sign of potential illness.  Alternatively, over-grooming can indicate that the cat is very stressed out, anxious, in pain, or has allergies. Before bringing your cat home, pick out a local veterinarian and schedule a visit within the first couple of days of its arrival.  Be sure to ask for any medical records from the shelter or breeder!  Get your house in order and buy everything that the cat will need in your home.  For a list, see "Things You'll Need" below.
Research the temperaments of different breeds. Consider the cat age that is most appropriate for you. Find a cat whose personality is a great match with yours. Discuss introductions with the breeder or shelter. Check for obvious signs of illness. Start preparing for your cat to come home.