The simple answer is, just about anything you want to, within reason and safety limitations, or course, but the choices of style, cost and application make it virtually limitless as to the different possibilities.  While most people are no doubt familiar with common light strings such as rope lights and similar products, there are many more options to choose from, and many of these are actually more affordable than one would think.

Decorations

The most popular use for outdoor string lights is in decorating backyards and businesses for a host of special occasions and gatherings as well as just for the ambiance and utility or security lights.  Online outlets like www.PartyLights.com specialize in a wide selection of outdoor lighting,
string lights patio and deck applications as well string lights with a huge range of covers and colored bulbs.  These are popular options for seasonal and sports-related events, or matching them with glass table tops and other outdoor furniture, and nothing says team spirit like a collection of helmets lit-up and dangling everywhere you look.

Getting Noticed

While the commercial applications have the same uses for the decorative aspects, there are much more profitable uses, as well as ways to get commercial outdoor string lights to pay for themselves.  Merely having a business lit-up with outdoor string lights will attract attention from miles around, and for much less than typical advertising would cost for the same returns.  Outdoor string lights commercial uses typically cost more, as these have to be heavy-duty designs and often involve larger power needs and support structures for safety and the most coverage.

Fun and Celebration

Outdoor string lights are also great for just plain fun and entertainment, and for this reason, many people keep some form of string or rope lighting up year-round.  Colored strings, shapes and even lettering patterns can add to the fun, although, the more extravagant the layout, the more expensive the overall lighting costs will be.