Scale represents a fraction of real size.
A vehicle that is 16 feet long in real life, will be 1 foot long in 1/16th scale.

Big 1/16 Farm Toys
Older farm tractors are 8 to 10 inches long, many newer models are more than 12 inches long, you are about 4.4 inches tall. Most are great for kids.  Collector and Precision models are intended for display rather than play.
1/18 Cars, Pickups The 'typical' car is about 12 inches long. Most are designed for display and have small, breakable pieces.
Cars and Trucks Cars are 8 to 10 inches long, trucks are 12 inches or more. Most items are built for older children or for adult collectors.
Farm Toys, Trucks  Farm tractors are smaller but still big enough for little hands. Old semi rigs are 14-16 inches long.  You are just over 2 inches tall. Most items are suitable for play.
1/43 Farm Toys, Cars, and Trucks. The same scale as a Lionel railroad.  Trucks and cars are 3.5 to 4.5 inches long. Great for older children, many items have small parts.
1/48 Airplanes Common scale for smaller airplanes and military models. Some suitable for older kids.  Mostly collectibles.
1/50   Construction Toys and Trucks Dozers are 5 or more inches long, graders and scrapers are 6 inches or more, cranes and large excavators are 8 to 12 inches and up.  You are about 1.4 inches tall. Mostly for adult collectors and modelers.
1/64 Wide variety Farm tractors are between 3 and 4 inches long, a semi tractor with trailer is about 12 inches long. Great for all ages.  Small size makes this scale popular with kids and collectors.
1/72   Airplanes Popular scale for airplanes.  Still too large for modern bombers and passenger jets. Some suitable for older kids.  Mostly collectibles.
1/87 Wide variety Same scale as HO railroads.  Large variety of trucks, equipment, and accessories available. Great for anyone old enough to have an HO train set.
Small 1/144   Airplanes Common scale for larger planes. Some suitable for older kids.  Mostly collectibles.
1/160   Wide variety Same scale as N scale railroads.  Very small for most models. Strictly for collectors and railroad enthusists.