The "real estate" that your stateroom occupies, no matter the type, can make you seasick or keep you up all night with noise -- or it can lull you like a baby and provide exquisite views of your surroundings. That is why doing your homework is important. Here are some factors to consider when picking your cabins location on the ship.
Exception: Royal Caribbean and other cruise lines will also use sub categories to distinquish between how many occupants the cabin will sleep. Therefore a cabin that can sleep up to 4 people will be a different sub category from a cabin that sleeps only 2 people.
Exception: Carnival has several cabins which are classified as inside cabins but actually have a french glass door which allows light into the room (no balcony, but the door can be opened). Carnival also has some cabins that have a window, but because the window has an obstructed view (that means there is a railing or object in the way) it is listed as an inside cabin. Royal Caribbean has some cabins that have a window but look out over an inside promenade area. These are called "promenade staterooms".
On many ships, basic inside and outside cabins are usually the same size, the difference being that one has a porthole or picture window to let in natural light. Balcony cabins can also be the same size as standard insides and outsides, with the addition of the outdoor space on the verandah; sometimes the interior space is larger. A basic cabin, regardless of category, is referred to as a "standard" unless there is something about it that makes it different (such as physical layout, being handicapped accessible or a designated family cabin). With minisuites on up, you get bigger and bigger indoor and outdoor spaces.
stateroom on a cruise ship
cruise suites floor plan
carnival cruise room layout