TR4W (TR for Windows) is a freeware program for operating in ham radio contests. Approximately 80 percent of the program is based on source code of the TR LOG MS-DOS program, kindly provided by Larry Tyree, N6TR (author of TR LOG). The basic idea of the TR4W project is porting TR LOG code to the Windows environment. TR4W is written in pure Windows API (application programming interface) and designed to be as small and fast as possible. Size of the executable file is only 170 kB. The TR4W project was started in March 2006, by Dmitriy Gulyaev, UA4WLI.