ICE 3 in the context of "Multiple-unit"

A multiple-unit train (or multiple unit (MU)) is a self-propelled train composed of one or more carriages joined, and where one or more of the carriages have the means of propulsion built in. By contrast, a locomotive-hauled train has all of the carriages unpowered.

An implication of this is that all the powered carriages needs to be controllable by a single engineer or driver, which is a case of the broader concept of multiple-unit train control. In other words, all "multiple units" employ some variation of multiple-unit train control. In the broader context "unit" means any powered rail vehicle, including locomotives (that does not carry cargo) and powered cargo-carrying carriages. In the context of this article, "unit" refers specifically to the latter only (whether the cargo is passengers or some other cargo).

Intercity Express (commonly known as ICE (German pronunciation: [iːtseːˈʔeː] ) and running under this category) is a high-speed rail system and service in Germany. It also serves destinations in Austria, France, Belgium, Switzerland and the Netherlands as part of cross-border services. It is the flagship of the German state railway, Deutsche Bahn. ICE fares are fixed for station-to-station connections, on the grounds that the trains have a higher level of comfort. Travelling at speeds up to 300 km/h (190 mph) within Germany and 320 km/h (200 mph) when in France, they are aimed at business travellers and long-distance commuters and marketed by Deutsche Bahn as an alternative to flights.

The ICE 3 also has been the development base for the Siemens Velaro family of trainsets which has subsequently been exported to Renfe in Spain (Renfe Class 103), which are certified to run at speeds up to 350 km/h (220 mph), as well as versions ordered by China for the Beijing–Tianjin intercity railway link (CRH 3) and by Russia for the Moscow–Saint Petersburg and Moscow–Nizhny Novgorod routes (Velaro RUS) with further customers being Eurostar as well as Turkey and Egypt.