Originally posted by Lzel How much distance would that be in feet?
If you are thinking of distance to the subject, that's another issue entirely. The 18-55 DAL kit lens can focus on any distance from roughly 1 foot to infinity. Most lenses go to infinity; their shortest focus distance varies, but it doesn't much depend on their focal length.
The focal length determines the magnification of the lens, and its field of view. Those are related inversely. When you make a subject look twice as tall, only half as much of it will fit into the picture. So you tend to want a long focal length with small and/or distance subjects, to make them big enough to see, and a short focal length with large and/or close subjects, to fit them all in.
You'll become familiar with what the numbers mean over time. As a rule of thumb, 30mm is about neutral, neither artificially wide field of view nor artificially magnified size. The magnification is directly proportional to the focal length. 300mm will make the subject look 10 times as tall as 30mm, and roughly corresponds to what you'd see with a pair of 10x binoculars. 15mm will make the subject look half as tall, but you'll include correspondingly more of it in the picture.
18-55mm thus includes the middle, 30mm; and zooms in to 55mm which is nearly x2, ie subject nearly twice as tall; and out to 18mm which is nearly x0.5, ie fitting nearly twice as much of the scene into the picture. It's a useful, every day range.