Edging your landscape has various forms and can be seen differently. This can be interpreted in two ways.
Firstly, edging your whole landscape can mean that you surround your whole landscape with a fence which can be made out of wood or boards. You can choose the color of the fence to match your house or use this feature to make it more interesting. Also one opportunity of edging your landscape is to border with tight hedge of bushes. This covers your yard or whatever landscapes you are edging from the eyes of other beholders who should not see in there.
The other way of understand landscape edging is that there are different ways of how to frame various parts and features of your landscapes. This means a big variety of corner pieces to surround your lawn or different edges for flower beds or trees and bushes. This can be an interesting feature of your landscape and make the maintenance easier as edging helps to stop your flowers spreading to grass and vice versa.
Of course you can use the both ways of landscape edging as it depends on your personal preferences and what you think suits into your landscape.