Where You Lay Your Head: What do you know about mattresses?

According to The Better Sleep Council, Egyptian pharaohs began using raised pallets around 3400 BCE.

The introduction of cotton mattresses helped keep bugs out of beds. Cotton was less attractive to insects than the materials previously used to stuff mattresses.

A California king is not the same size as a regular king-size mattress. A California king measures 72 inches by 84 inches, which is 4 inches longer and 4 inches narrower than a standard king-size bed.

Most homes and hotels have innerspring mattresses. They're generally less expensive than foam and high-end air mattresses, so they're a popular choice for many people.

Waterbeds are true to their name. They actually contain water! Some people prefer waterbeds because they shape to the sleeper's body, and they don't collect dust and other allergens the way innerspring and foam mattresses do.

Experts recommend getting a new mattress at least every 10 years. Some recommend replacing an old mattress sooner, but most agree that you don't want to keep an innerspring or foam mattress for more than 10 years.

A good mattress should support your spine, not try to straighten it while you sleep.

Flip and rotate your innerspring mattress every few months to keep it from becoming indented and saggy in certain places.

Don't worry about a mattress looks like -- focus on what it feels like. It doesn't matter if the mattress is blue, white or peach because you're going to take it home and put sheets, blankets and pillows on it. Pick out a mattress that's comfortable for you, and don't worry about how it looks.

While mattresses may not be the easiest thing in your home to clean, it's not impossible to get the job done. Regularly vacuuming your mattress will help keep it clean and remove dust and other allergens.

Consumer Reports recommends that shoppers spend between 15 and 20 minutes lying on a mattress to see how it feels. Yes, you might feel odd lying down in a store, but that's much better than being uncomfortable for years in your next bed.

It's recommended that adults get six to eight hours of sleep every night. Getting this much sleep can have profound health benefits, including lowering your risk of depression and heart disease. In other words, get some rest!

Mattress stores put their products on sale regularly, so if you're in the market for a new mattress, look for good deals on the type of bed you want to purchase.

Futons are a type of bedding that can be folded and put away or used as a couch during the day. Futons have become popular in the U.S. because they're typically less expensive than sofas.

Firm mattresses are good for some people, while softer mattresses are better for others. You have to figure out what's best for you!

Couples who don't see eye to eye on mattress firmness often decide to purchase mattresses with two separate air chambers that inflate and deflate depending on the preferred firmness level of the sleeper.

Many charities do not accept used mattresses because of the dirt, dust and other allergens they collect. Unfortunately, millions of mattresses end up in landfills every year, even though they contain a lot of recyclable material. Instead of throwing yours to the curb, search the Internet for recycling centers that will let you drop off your old mattress.

United States law requires that all new mattresses have a tag guaranteeing the consumer that the product is new. Once you own the mattress, you can remove this tag without facing any legal penalties.

Two twin beds put together will give you the width of a king-size bed but not the length. King-size beds are 5 inches longer than twin beds.

A pillowtop mattress is a bed that comes with a layer of padding on the top of the bed for extra cushioning.