Back in 1994, Chris Sawyer released the game Transport Tycoon, which was published by Microprose. The following year (1995), a revised and updated version of the game called Transport Tycoon Deluxe (with the option for one-way signals, and some added environments) was released.
Transport Tycoon was a very popular simulation game which allowed players to build road, rail, sea and air transportation networks, moving passengers, mail and a variety of goods, either in free-play form (with or without computer opponents) or in an attempt to meet targets specified by scenarios.