The "Bullet Train" is an informal name for the Shinkansen, a network of high-speed inter-city railway lines in Japan operated by four Japan Railways Group companies. They are called "bullet trains" because of their elongated, tapered metal appearance, which resembles a speeding silver bullet.
Shinkansen means "New Main Line." The tracks are designed with no level crossings or other obstacles. The trains are very fast and remarkable for their quietness. There are three train categories: Nozomi, the fastest and most expensive, with 100-percent-reserved seating; Hikari and Kodama. Multiple lines criss-cross the country, and most trains run on tracks exclusively built for and used by Shinkansen trains.