MARS (マルス, Marusu), which stands for Multi Access (originally Magnetic-electronic Automatic) seat Reservation System, is a train ticket reservation system used by the railway companies of former Japanese National Railways, currently Japan Railways Group (JR Group) and travel agencies in Japan, developed jointly by Hitachi and the Railway Information Systems Co., Ltd (JR Systems), a JR Group company jointly owned by the seven members of the group.[vague]
The host of the system is located in Kokubunji, Tokyo, and managed by JR Systems.
Ticket offices at JR stations equipped with MARS terminals are called as Midori no Madoguchi (みどりの窓口, literally "green window"), selling tickets of all JR Group trains and partly highway buses and route buses and ferries. It is possible for passengers to reserve tickets of buses and trains from one month prior to ride on.
Now, the Midori no Madoguchi is named by JR Group excluding JR Tokai.
The MARS-1 system was created by Mamoru Hosaka, Yutaka Ohno, and others at the Japanese National Railways' R&D Institute (now the Railway Technical Research Institute), and was built in 1958. It was the world's first seat reservation system for trains. The MARS-1 was capable of reserving seat positions, and was controlled by a transistor computer with a central processing unit consisting of a thousand transistors.
The latest version of MARS uses the MARS 501 system which was introduced in 2002.