A Wall or Fascia Sign attaches to the exterior wall or fascia of a building and often has an illuminated face.

A Blade or Projecting Sign is mounted on a building, but the sign extends at a perpendicular angle and is often double-sided. 

Hanging or Suspended Signs are exactly what they sound like - signs that hang from the ceiling of a building, awnings, etc.

Monument Signs are large freestanding signs located at an entrance of a property and often lower in height than many signs.

Pole Signs are very large freestanding signs with a visible support structure. A Pylon Sign's support structure is enclosed.

Post Signs are freestanding signs that have one or more visible posts and are often made of either cabinets or panels.