How to pick the perfect cruise

In general, the bigger the ship, the more it offers in terms of deck-top amusements. Royal Caribbean"s Allure of the Seas has a zip line that takes riders across an open-air atrium nine decks above the sea. But if being around crowds isn"t for you, reconsider this ship: it can carry more than 6,000 people.
Where do I want to go?
It wasn"t long ago that most cruises took place in the Caribbean. But these days, even the most mainstream lines offer sailings around the globe. Still, not every line goes to every destination. And some lines are stronger than others in particular areas. In Alaska, for instance, two lines — Princess and Holland America — dominate with seven ships apiece. (Industry giant Carnival, by contrast, has just one ship in the state.) The result: Princess and Holland America can package trips to Alaska in a way most other lines can"t. Carnival, on the other hand, always has been a leader in the Caribbean, with more voyages there from more home ports than any other line.
How long do I want to be away?
This can have a huge influence on which line — and ship — you choose. Some lines, such as Carnival, specialize in shorter cruises of three to seven nights. Others, such as Oceania, rarely offer a voyage of fewer than 10 nights. On the far end of the spectrum, a few lines such as Cunard and Holland America operate annual around-the-world cruises of 100 nights or more.
What"s my budget?
Like hotels, cruises come in a wide variety of price points with features to match.
Mass-market lines such as Carnival offer voyages for as little as $399 per person, per week. Luxury lines such as Seabourn and Regent Seven Seas can charge as much as $1,000 per person, per day. Rates can swing significantly depending on the season (the same cabin on the same ship will cost a lot more during the peak summer travel season than in the fall). And the lead-in price you see in ads often is for a small, "inside" cabin without windows onto the sea. You might pay hundreds of dollars more for an outward-facing cabin with a balcony.
What"s my cruise personality?
Every line has its own personality — and appeals to a different type of person. Carnival, for instance, is known for a gregarious, fun-loving crowd. Celebrity, by contrast, draws a quieter, more style-conscious customer. The two lines operate ships of similar sizes, and often on similar routes and at similar prices, but a regular Carnival customer would likely be miserable on a Celebrity ship — and vice versa.
How important is the food?
Dining always has been a big part of the cruise experience, and all of the lines pride themselves on their selection of restaurants. That said, some cruise lines place far more emphasis on food than others. Lines such as Oceania, Cunard and Crystal have brought in big-name chefs (Jacques Pepin, Todd English and Nobu Matsuhisa, respectively) to design eateries. And diversity also varies widely, with some lines such as Royal Caribbean and Norwegian offering more than a dozen eateries on some ships.
Will I get seasick?
Modern cruise ships are built for stability, with new technologies such as stabilizers that make for smoother sailing than the vessels of a couple decades ago. Weather prediction also has improved, so the captain can know bad weather is ahead and cruise around it. However, the ocean is still unpredictable, so go with a bigger, smoother-riding ship that sails in calmer waters (such as the Caribbean rather than the North Atlantic) if you are prone to seasickness.