What's a Bevel?
Many of my tutorials refer to making a "beveled" edge on something, or adding a "bevel" to a flat surface. Essentially, a bevel is a rounded out corner. Check out this illustration...
It shows a piece of a Star Trek PADD from the side. The top illustration shows the squared off edges on the top. It has no bevel. After attacking this piece with some sand paper, a file, a dremel, or a router, the bevel is added. The second illustration shows how the edge on view of the padd will look with the beveled edge.
Heck, even the Mirriam Webster online dictionary has a good little picture. Check it out
That's it!