Cat Cats love to climb and scratch a lot of stuff. Buy them something that combines climbing and scratching. They don't need much attention when their old.
Dog Dogs love playing outside or inside. They love playing with toys too. Give them lots of attention. Find something to give to them or they'll find your shoes...
Bunny Bunnies love carrots and little houses to hide in. When you adopt a bunny they will hide in there because they are scared or a little shy at first.
Hamster Hamsters love to curl up in your hand because it just like there bed but bigger and nicer. They love to climb, just like guinea pigs, in there little tunnels.
Guinea Pig Guinea pigs love to play with you. Even if you are playing XBox, they'll still want to play with you. Guinea pigs are very loyal and stay by your side once they get to know you.
Chinchilla Chinchillas are very fluffy and love to be held by people, they mostly don't like other animals. But other wise they make the perfect pet if your a night person.
Snake Snakes love to climb up things. Like, bodies, chairs, tables, anything! When you first get a snake, buy them a pole, that doesn't fall, so they can slither up it.