A railfan, rail buff or train buff, railway enthusiast, railway buff or trainspotter, is a person who is recreationally interested in trains and rail transport systems.
Railfan photographers in Belgium in September 2003, at the farewell of the NMBS/SNCB Class 51 locomotive
Bill Nye looks over the model railroad display at the Pasadena, California model train club
A trainspotter photographing an N700 Series Shinkansen on the Tokaido Shinkansen line near Mount Fuji
Railfans taking train photos at the Japan Railways Group (JR) Tokyo train center
A scanner is a radio receiver that can automatically tune, or scan, two or more discrete frequencies, stopping when it finds a signal on one of them and then continuing to scan other frequencies when the initial transmission ceases.
An Icom IC-R5 hand-held scanner
A GMRS radio that also has scanning capabilities
A Uniden BCT-15 base trunktracking scanner
A Uniden scanner installed in a vehicle. Some US states prohibit this unless the operator has an FCC issued radio license