Clogged drains are an annoying but common household problem. Unclogging a blocked sink or bathtub usually involves fishing something unappealing out of the pipe, if professional plumber isn't available. The best thing to do is to prevent clogging in the first place. Here are five things that can block up your drains if you're not careful:

1. Hair

Hair is one of the leading causes of clogged drains. It's also one of the most preventable. Wet pieces of hair get snarled up together easily, and before you know it, there's a hairball lurking somewhere in your pipe. If you have long hair, or if you live with someone who does, it's a good idea to get a hair catcher for your bathtub drain.

2. Soap

When you dump soapy water down a drain, a tiny bit of soap scum sticks to the sides of the pipe. Over time, this soap scum builds up more and more, preventing water from draining as efficiently as it used to. Add hair to the mix, and you've got the recipe for a clogged drain - hair sticks to the soap and catches more hair, creating a gunky mess. You can clear soap scum out of your pipes before it becomes a problem by pouring boiling water (or, if that doesn't work, ammonia) down the drain.

3 Grease

Grease is another common drain-clogger. Like soap, it builds up in your pipes over time and catches other particles of stuff that get rinsed down the drain. Grease is especially bad for your pipes if it hardens when it gets cool, therefore you should never pour leftover melted shortening down the drain. Dispose of oil by letting it cool and scraping it into a trash bag instead. If you do happen to pour grease down a drain, you can prevent it from clogging by flushing out the pipe with boiling water.

4. Food

Don't rinse food particles down the drain. Sticky, mushy foods like potatoes and rice, can clump together and cause blocked drains, especially if there's already grease in the pipe. Clean out your sink strainer regularly, and be careful not to let any food remnants go down with the dishwater.

5. Pipe damage

Sometimes there's not much you can do about a clogged drain. If a pipe gets damaged — for instance, by a tree root that causes it to shift position — your sinks may not drain properly. If you've tried to fix a clogged drain and nothing works, a damaged pipe could be to blame. This problem is not always easy to trace and repair on your own, so call an expert out to take a look.

Nobody likes unclogging a drain. Luckily, most clogs are preventable, and there are a few simple things you can do to help keep your pipes unobstructed. Avoid the pipe-clogging culprits on this list, and (barring bad luck) your drains will stay clear for years to come.