Operations

A railway can be broken down into two major components. Firstly, there are the items which "move", also referred to as the rolling stock, which include locomotives, passenger carrying vehicles (or coaches), freight carrying vehicles (or goods wagons). Secondly are the "fixed" components, usually referred to as the railway's infrastructure, including the permanent way and ancillary buildings that are necessary for a railway to function.

Rolling stock

A locomotive is the vehicle that provides the motive power for a train. A locomotive has no payload capacity of its own, and its sole purpose is to move the train along the tracks. Traditionally, locomotives pull trains from the front.
A railroad car is a vehicle used for the haulage of either passengers or freight. Most cars carry a "revenue" load, although "non-revenue" cars exist for the railroad's own use, such as for maintenance-of-way purposes.

Signalling

Railway signalling is a system used to control railway traffic safely to prevent trains from colliding. Being guided by fixed rails, trains are uniquely susceptible to collision since they frequently operate at speeds that do not enable them to stop quickly or, in some cases, within the driver's sighting distance.

Most forms of train control involve movement authority being passed from those responsible for each section of a rail network (e.g., a signalman or stationmaster) to the train crew. The set of rules and the physical equipment used to accomplish this control determine what is known as the method of working (UK), method of operation (US) or safeworking (Aus.). Not all methods require the use of signals, and some systems are specific to single track railways. The signalling process is traditionally carried out in a signal box or interlocking tower, a small building that houses the lever frames required for the signalman to operate switches and signal equipment. These are placed at various intervals along the route of a railway, controlling specified sections of track. More recent technological developments have made such operational doctrine superfluous, with the centralization of signalling operations to regional control rooms. This has been facilitated by the increased use of computers, allowing vast sections of track to be monitored from a single location.

Right of way

Railway tracks are laid upon land owned or leased by the railway. Owing to the requirements for large radius turns and modest grades, rails will often be laid in circuitous routes. Public carrier railways are typically granted limited rights of eminent domain (UK:compulsory purchase). In many cases in the 19th century, railways were given additional incentives in the form of grants of public land. Route length and grade requirements can be reduced by the use of alternating earthen cut and fill, bridges, and tunnels, all of which can greatly increase the capital expenditures required to develop a right of way, while significantly reducing operating costs and allowing higher speeds on longer radius curves. In densely urbanized areas such as Manhattan, railways are sometimes laid out in tunnels to minimize the effects on existing properties (see condemnation).

Safety and railway disasters

Trains can travel at very high speed; however, they are heavy, are unable to deviate from the track and require a great distance to stop. Although rail transport is considered one of the safest forms of travel, there are many possibilities for accidents to take place. These can vary from the minor derailment (jumping the track), a head-on collision with another train and collision with an automobile or other vehicle at a level crossing/grade crossing. Level crossing collisions are relatively common in the United States where there are several thousand each year killing about 500 people (the comparable figures in the United Kingdom are 30 collisions and 12 casualties). For information regarding major accidents, see List of rail accidents.

The most important safety measures are railway signalling and gates at level/grade crossings. Train whistles warn of the presence of a train, while trackside signals maintain the distances between trains. In the United Kingdom, vandalism or negligence is thought responsible for about half of rail accidents.[citation needed] Railway lines are zoned or divided into blocks guarded by combinations of block signals, operating rules, and automatic-control devices so that one train, at most, may be in a block at any time.

Compared with road travel, railways remain safe. Annual death rates on roads are over 40,000 in the United States, about 3,000 in the United Kingdom and 900 in Australia, compared with 1,000 rail-related fatalities in the United States,under 20 in the UK and 10 in Australia. (These figures do not account for differences in passenger-miles traveled by mode; see e.g. Transportation safety in the United States.)