The design of many different fences these days rely on two very different priorities. One part of it consists of creating a design where form is the main issue at hand, while the other deals with designing out of a need for function.
The design of fences where form is considered the main function involves a lot of dealing with the material from an aesthetic point of view. In such cases, the designer of the fence will also deal with its installation and how it would work with the rest of the landscape and fauna. For example, picket style fences, although functionally sound, may be preferred over other types of fences when it comes to fencing a cottage style home with a beautiful garden. A split rail wood fence may also be used for a ranch style home with a beautiful porch in order to convey a good, old-fashioned country feel. Steel fences may also be preferred for more modern homes and structures.
Designing fences with function in mind deals with using the materials not for their aesthetic value, but for their practical applications instead. In such cases, wood might be preferred as the material for durability and hardiness while chain link fences might be the preferred in areas where visibility both from the outside and the inside is crucial.