With manufacturers adding a dizzying number of derivative models to their lineups, classifying the available crop of business jets is becoming harder than ever. In an attempt to make better sense of the groupings, Business Jet Traveler uses cabin volume as the chief attribute defining the cutoff points for each category. After all, the first thing you usually notice when stepping aboard an airplane you've not been on before is how spacious-or cramped-the passenger quarters are.

According to our criteria, personal jets such as the Diamond D-Jet are on the bottom rung. Compact jets such as the Eclipse 500 are next, followed by categories for small, midsize, super-midsize and large jets and, finally, bizliners like the Boeing Business Jet and Airbus Corporate Jet.

Classifications by weight, range and price are used to further define the categories when needed. This means we still use terms like "very light jet" and "ultra long range" where appropriate, but interior room is considered the top trait. And for good reason: research by aircraft manufacturers has shown that the size and comfort of the passenger compartment is often judged to be the most important attribute of a business airplane.

The chart (link below) lists popular business jet models by cabin size.