I agree with all that Culture Junky says. My cats have both purchased and impromptu toys, and they love both. They need exercise to keep their insides moving properly. They need stimulation so they don't get bored, fat, and in trouble.

Use caution in which toys you leave for the cat to play with unsupervised. Feathers may get caught in their throat and should only be part of a toy out for play when you are watching. Yarn is a NO-NO! Cats have little hooks on their tongues and there is no way they can put yarn down, so they end up eating it. Lots of problems internally then.

Straws, plastic strips from milk bottles, small hi bounce super balls all work fine. Toy mice with a catnip scent and little rattle noise from inside are a favorite of my cats. Just watch when they have cracked it, time to throw it away; you don't want them eating whatever is inside making the rattle sound.

The fishing rod style toys (and others) allow interaction with you; this is also important.

My cats have so many toys we have a toy box; I rotate their toys whenever I notice one which hasn't been used for a day or so. The toys in the box often are in a container with some catnip so they pick up the scent for next release. I had to move the toy box into a closet, because Crystal learned how to open it and started helping herself! I would come home to a tipped over empty box and toys throughout the house!