If you own a Rolex watch, beloved jewelry or a baseball signed by Joe DiMaggio, you should also have a safe.

"We all have valuables, even if their value is just sentimental," says Ray Miller, a security consultant in Los Angeles. "When people buy and start using a safe, they often feel they were lucky all those years they didn't have one."

Trying to pick from the thousands of home safes on the market can be daunting. Safes, which run from $40 to more than $1,000, are designed to protect their contents from fire, theft or both. Here are some of the most common models:

Fire safes: Most people choose these types of safes because they're the cheapest. Companies make the casing of these safes by sandwiching diatomaceous earth between two sheets of metal. The material insulates the valuables and keeps them from turning into ash in a fire. These safes can withstand anything from a half hour of 1,550-degree heat to two hours at 1,850 degrees.

Special handling is required to protect film, software, tapes and other electronic media. Companies make small containers that maintain internal temperatures of less than 125 degrees to safeguard this kind of equipment. Fire safes work by releasing steam into the compartment, which keeps everything from burning, which is why it's a good idea to encase any important papers in plastic to protect them from water damage.

Burglary safes: Underwriters Laboratories tests safes to gauge their resistance to theft, and then rates them. A "TL-15" rating means it took 15 minutes for a lab technician to break into the safe. Boxes with the highest rating, "TL-30x6," protected their contents for at least 30 minutes on all sides.

We're accustomed to seeing safes in movies with biometric locks that require a person's thumbprint to access, but most home-safe locks are digital or use an old-fashioned combination dial. A top-quality safe can lock itself if someone takes too long to enter the right combination or tries to pry it open. High-end burglary safes often have a fire rating, giving you more protection.

Wall safes: Burglars in movies look for wall safes behind paintings in their search for loot. In reality, they tend to be shallow because they have to fit within a wall that's probably not more than six inches thick. While they're not considered as secure as other safes, they're convenient and their shape is ideal for hiding documents.

Standalone safes: Most people think of these heavy boxes when they hear the word "safe." However, some manufacturers design safes that can be concealed inside a piece of furniture. They might cost more than the valuables they protect, but they're the safe of choice when you have expensive items to hide.

Floor safes: Security professional often choose these safes for their homes. They're typically installed into the floor, and covered by furniture or a heavy object. Some companies encase these safes in concrete during installation to make them immobile.