Routine household maintenance has stayed the same in some things, but there are some new things to try to remember that can save you money on repairs or early replacements. One of the biggest is to clean a computer regularly, at least once or twice a year. The frequency probably depends on the amount of dust, pet hair, and smoke in your home. If you dust regularly, but knock it down onto the computer or stir it up into the air, you probably need to clean the computer more regularly too.
Keep in mind, I'm not a computer expert. On the other hand, I do speak English most of the time when talking about computers. So, why clean the dust out of the computer? It can cause overheating, particularly if it clogs up a cooling fan, slowing it down. That can cause the computer to run more slowly or parts to burn out entirely, which can be a very expensive repair if the motherboard goes.
You need a can of compressed air and a screwdriver. Turn off the computer and unplug it. I'd recommend giving it a few minutes to cool off first, and some people do this outside so they don't spray dust all over the place. Remove the cover (that's why you need a screwdriver). Use short bursts to blow the dust out. Most computer cases have a grill at the back, so that can be a good direction to aim so the dust leaves the computer.
If your computer was particularly dusty or had a lot of pet hair in it, you probably want to plan to dust more often. Me, I aim for at least once every 3 months.