Cruise ships range in size from a capacity of dozens of passengers, all the way up to well over six thousands people.  That is the population of a small city.

All of those people have to live on a cruise ship for a few days, or even a week or longer. They expect nice conditions in well-kept staterooms where they take a shower and use a private toilet. These facilities use water, which may not seem like much individually, but it soon adds up.

So where does all that water go once it goes down the drain or toilet?

Ever wonder how a cruise ship works?

A new cruise ship costs well over one billion dollars, and will only last a cruise like around 20 years. There are then costs for maintenance, food, fuel and crew members.

If you think the cruise fare covers all of those costs, think again. It is not uncommon for cruise fares to dip as low as $60 or $70 dollars a day, so how can these ships ever be profitable?

Canada has dominated cruise-related headlines in recent weeks, due to the yearlong extension of its cruise ship ban, which is now set to expire February 28, 2022.

The move prohibits passenger vessels carrying more than 100 people from entering Canadian waters. It also jeopardizes 2021's North America-based voyages to Alaska and New England.

Can you get married on a cruise? The answer is a resounding "Yes!" Cruise lines make it easy by offering a number of packages at varying price points, but there are still some things you should know.

Check out our tips for how to plan a wedding on a cruise.

1. Do your research.

Although some brands are known specifically for romantic cruises for couples, there are plenty of romantic things to do on a cruise with any line.

Here, we'll help you craft the perfect "I've got butterflies" voyage for you and your partner.

1. Splurge on a suite.

Just because you're on vacation doesn't mean there aren't rules. Want to know how old you have to be to stay in your own room, purchase alcohol or gamble? We've got you covered with our roundup of cruise line age policies.

Below, check out key age-related policies for each of the eight most popular cruise lines.

Minimum Age to Cruise

Whether you're a smoker or someone who has never so much as touched a cigarette or cigar, you might be wondering about cruise ship smoking policies. We'll answers some of your biggest smoking-related questions.

Can I smoke on a cruise?

Cruise planning and research are head-spinning if you haven't done them before. From narrowing down a cruise line and ship to choosing a destination and booking shore excursions, learn how to get started.

Below, we've outlined 10 key factors to consider when building your ocean-bound vacation. Although they're all important, their order might fluctuate depending on your circumstances, and any one of them can be affected by others -- if your budget limits your destination choices, for example.

You've decided on a cruise for your next vacation, and you've narrowed down the destination, sailing date, ship and cabin type. What now? We'll lead you through the best way to book a cruise.