1. Fixed billboards:
(1) Large advertising boards, mainly referring to building exterior wall billboards, which generally cover a large area. The area of one advertising board can sometimes even exceed 500 square meters.
(2) Sidewalk advertising signs, which refer to small boards, light boxes, pillar advertisements, or directional signs posted on both sides of the sidewalk, usually at a short distance of 2-5 meters from the ground and relatively low. They effectively spread information.