Illegal signs: A sign or billboard unlawfully placed or maintained. The OAAA supports an removal of illegal signs without compensation.

Illuminated panel: Outdoor media structures equipped with lighting to illuminate the display face.

Imprint: Name of the outdoor media provider attached to the advertising structure.

Inflatables: Gas-filled, three dimensional displays for use at points of sales or special events; usually it takes the shape of the product or trademark character.

Inside panel: All panels grouped at one location facing the same direction except the one closest to traffic (end panel).

Inspection: A tour of outdoor media structures for pre-buy selection, or post-buy proof of performance.

Intensity: Level of advertising weight, determined by the outdoor media provider. Referred to as GRP Showing, common sizes are #21 #50, #75 and #100.

Internet: Online network of computers; include World Wide Web which is used by outdoor media industry as an interactive service for market data, inventory listing, video drive bys, sales transactions as well as other uses.