Canon created a guide on digital SLR cameras. First they take a closer look at dSLR cameras, then they learn you how to shoot pictures by taking a look at some advanced features and they end with a printing guide. Here's a short snip:
Wonder why your picture looks out of focus?
There is a point of sharp focus, and any object in the front or back of that point will look unsharp. The further away it is from the point of focus, the more blurry it will look. The area that looks sharp is "in focus," while the areas that are not sharp are "blurry." If an area looks blurry, it is out of focus. With a digital SLR, use autofocus to focus at the desired spot. (See pages PART 3-08~11 for the focusing procedure.)