, or STi, is Fuji Heavy Industries

Fuji Heavy Industries

, or FHI, is a Japanese transportation conglomerate most known for being the manufacturer of Subaru automobiles. It traces its roots to the Nakajima Aircraft Company, a leading supplier of airplanes to the Japanese government during World War II...

' motorsport

Motorsport

Motorsport or motorsports is the group of sports which primarily involve the use of motorized vehicles, whether for racing or non-racing competition...

s division. STi, along with Prodrive

Prodrive

Prodrive is a British motorsport and automotive engineering group based in Banbury, Oxfordshire, England. It designs, constructs and races cars for companies and teams such as Subaru, Aston Martin and Ford...

 of the UK specializes in the preparation of a variety of vehicles for the Subaru World Rally Team

Subaru World Rally Team

The Subaru World Rally Team was Subaru's World Rally Championship team. It used a distinctive blue with yellow color scheme that is a throwback to the sponsorship deal with State Express 555, a BAT cigarette brand popular in Asia. 555 logos were found on Subaru cars from 1993 to 2003...

 which competed in the World Rally Championship

World Rally Championship

The World Rally Championship is a rallying series organised by the FIA, culminating with a champion driver and manufacturer. The driver's world championship and manufacturer's world championship are separate championships, but based on the same point system. The series currently consists of 13...

 (WRC). It was founded in 1988 by Fuji Heavy Industries

Fuji Heavy Industries

, or FHI, is a Japanese transportation conglomerate most known for being the manufacturer of Subaru automobiles. It traces its roots to the Nakajima Aircraft Company, a leading supplier of airplanes to the Japanese government during World War II...

, the parent company of Subaru

Subaru

; is the automobile manufacturing division of Japanese transportation conglomerate Fuji Heavy Industries .Subaru is internationally known for their use of the boxer engine layout popularized in cars by the Volkswagen Beetle and Porsche 911, in most of their vehicles above 1500 cc as well as...

, to promote the company's performance-oriented identity.

STI's signature color has traditionally been "Cherry Blossom Red" (or "Rubine Red" as it's known in Australia.) It is seen as a masculine colour in Japanese culture.
While Subaru offers many models with a trim level labeled "STI" or "Tuned by STI," there have been several special limited edition STI models.