Dive lights can be used for night scuba diving, cave diving, or even diving on a rainy, overcast day. An advanced diver knows that sunlight -- or your artificial scuba dive lights -- will illuminate colors of fish and plant-life, making your trip much more spectacular. You may also encounter cracks or crevices teeming with wildlife that simply can't be seen without a light source.

Safety recommendations require that every cave diver must have three separate light sources available -- one main and two backups -- and if one of those should fail for any member of the team, all divers must call off the rest of the expedition.

A wide-beamed primary light will illuminate a large area and is ideal for overcoming total darkness, while a brighter, smaller secondary light will reveal the ocean's subtleties.

It's tempting to think that "brighter is better," but that's not always the case. If you're in water that has a lot of suspended particles floating around, then the bright light might illuminate all the wrong things and make it actually more difficult to see.

Underwater photographers won't want overly bright scuba dive lights either, as it will scare off fish and cause reflective hot spots in the pictures.

The daytime divers might be happy with a basic $30 LED light and cheap 45-minute incandescent bulb. However, underwater photographers, or cave and wreck divers will want a more intense scuba dive lights, like canister lights.

The 10 watt HID torch will give divers as much power as a 35 watt incandescent light and offers 4 hours of dive time on one charge, as well as the ability to use the light outside the water, without melting. These systems can cost as much as $800, but career divers wouldn't have it any other way.

Typically, people assume that rechargeable batteries are the way to go. However, with scuba dive lights, rechargeable batteries can fade very fast when they start to go.

While you'll get a more consistent light level from rechargeable batteries, a regular battery will likely last longer. Most divers use rechargeable batteries for daytime dives and regular batteries for nighttime diving (with the daytime light as backup).

Also, when choosing scuba dive lights, be sure they will last at least twice as long as your estimated dive time. Be sure to check the depth rating on them as well, to be sure it will hold up under pressure.

Be sure to purchase a cheap lanyard as the cheapest form of insurance against losing your light. Specialty mask lights are available for divers who want hands-free functionality.

Scuba dive lights are great for cave diving, wreck exploring, coral illuminating and even day time swimming. Lights can be a matter of safety or just personal preference.

You don't want to bombard wildlife with unnatural lighting, nor do you want to find yourself feeling freaked out and lost underwater in total darkness. Choosing the right light is important, so don't overlook the basics!