Beach Cruisers are all about style and just plain fun. There is no thought about speed or tricks or going for long distances. They are all about social and pictures and enjoying the view.
Beach cruisers are loosely a version of a cruiser. But this is really a distinction without a difference. You can ride your beach cruiser 100 miles from any beach on any road surface or easy trail, whether sand or dirt. And while cruisers are built to be tough and easy to maintain, they are not really designed for riding trails with rocks, roots, or difficult maneuvers. If the bike shop or church group is going on a 15 mile easy ride with no drops ... your good with your beach cruiser.
In the last few years, some manufacturers have added 7 speed gear set, heavy duty racking, and other extras for special purposes. These have morphed into urban bikes that are very much about utility rather than social.
When you are choosing a beach cruiser, think about the look you are hoping to achieve, just like you might choose a great outfit. Spend a few extra dollars to get better quality. You'll be happier in the long term.
Cruiser bikes generally have 26" wheels with heavy duty tires designed to work on any surface. You can buy smaller cruiser bikes designed for kids or the vertically challenged, and some of these have 24" wheels.
Don't forget to accessorize. Bells, horns, and baskets add to the romantic appeal of these fantastic bikes.