The exact ingredients that make up WD-40 are a closely guarded secret. The official WD-40 website says the product contains 50 percent mineral spirits, but this ingredient cannot adequately be called Stoddard solvent because of the refinement process used to make the product.
The name WD-40 stands for "water displacement 40th attempt." The name for the product came straight from the lab book that chemist Norm Larsen used when he created WD-40 in 1953. Larsen came up with this product while trying to create a formula that could prevent corrosion. To do this, he needed a product that could displace water. After 39 unsuccessful attempts, he got it right on his 40th try.
WD-40 was invented by the founders of the Rocket Chemical Company, one of whom was Norm Larsen. It was first used on the outer shell of the Atlas missile to help prevent corrosion. In 1958, WD-40 was repackaged in aerosol cans so that it could easily be sold to the public. The Rocket Chemical Company changed its company name to WD-40 in 1969 because this was the only product it ever made.
Although WD-40 is designed to help prevent corrosion, it has been used in many unique ways. For example, a police officer once used WD-40 to dislodge a naked burglar who had become trapped in an air conditioning vent, according to the WD-40 Company website.