A rack-and-pinion railway (also rack railway, cog railway) is a railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail. This allows the trains to operate on steep (slope) Most rack railways are mountain railways, although a few are transit railways or tramways built to overcome a steep gradient in an urban environment.

The first cog railway was the Middleton Railway between Middleton and Leeds in West Yorkshire, England, UK, where the first commercial steam locomotive, Salamanca, ran in 1812. This used a rack and pinion system designed and patented in 1811 by John Blenkinsop.

The first mountain cog railway was the Mount Washington Cog Railway in the US state of New Hampshire, which carried its first fare-paying passengers in 1868 and reached the summit of Mount Washington in 1869. The first mountain rack railway in continental Europe was the Vitznau-Rigi-Bahn on Mount Rigi in Switzerland, which opened in 1871. Both lines are still running.

The Greek is a fictional character on the HBO drama The Wire, played by actor Bill Raymond. The Greek is the head of an international criminal organization involved in narcotics and human trafficking. The Greek is a mysterious figure involved in numerous criminal activities. His given name is never mentioned on the show, and though he is known only as "The Greek", he has stated (in the episode Port in a Storm) that he is not actually Greek. A quiet and unassuming man, the Greek prefers to keep a low profile, operating all of his business through his lieutenant Spiros "Vondas" Vondopoulos. His smuggling organization operated from a small diner in Baltimore for years, and while Vondas would conduct business the Greek would listen in quietly at the counter. Nick Sobotka, upon seeing the Greek identify himself, was amazed that the shadowy figure had been in plain sight the entire time.

Despite his calm appearance, the Greek is cunning and ruthless, and only interested in facts that make him more money. Series creator David Simon has said that The Greek is an embodiment of raw unencumbered capitalism. Anyone interfering in this process is eliminated immediately, and he prefers to leave victims headless and handless to hinder identification.