Average ages on board vary by cruise line — and even from ship to ship — based on styles, tastes and itineraries. But there are cruise ships that provide activities and amenities for families with small children, young couples, groups of singles and, yes, even more mature travelers.

Today, ships feature stabilizers and are so large that you might not even notice you're moving, especially in the calmer waters of the Caribbean.

This highly contagious stomach bug is common on land — it's not actually a cruise ship illness. Sailings with outbreaks are not that typical, but regulations require reporting of the illness by cruise lines. So you're more likely to hear about it associated with cruises even though it's as common at resorts, schools, retirement homes, and large workplaces.

You can find many sailings that prove to be a better deal than land-based vacations, especially if you can drive to a port. Cruises start at around $75 to $100 per person, per day — even less during promotions.

If you get bored easily, choose a cruise ship that's packed with onboard activities that fit your personality. Some have Broadway-style shows, gourmet cooking classes, zip-lining, rock-climbing walls, water slides, bowling alleys, outdoor movies, comedy shows, dancing, and even surfing simulators.

This is actually a legitimate concern on the mega ships, which carry thousands of people. Still, those vessels are smartly designed and, if you prefer a bit of seclusion, you can always find a quiet place to relax away from crowds. In addition, small ships offer a way of avoiding crowds altogether.

This is only true on a few luxury lines. On most cruise ships, you have to pay extra for gratuities, specialty dining, excursions, spa treatments, drinks, and other onboard activities, not to mention flights, hotels, and transfers.