In 2364, the location of 61 Cygni was labeled in a star chart of a stellar neighborhood with Sol at the center. This chart was stored in the USS Enterprise-D library computer. Later that year, the chart was scanned by Outpost 63. (TNG: "The Naked Now", production art; TNG: "The Last Outpost")
The star chart naming stars within 20 light years of Sol was drawn by Rick Sternbach for the Star Trek Spaceflight Chronology in the late 1970s. Found on page 77, this chart showed Earth commercial and exploration routes after the use of warp drive began. 61 Cygni was the destination on an exploration route.
According to Star Fleet Technical Manual, the United Planets of 61 Cygni was one of the founding members of the Federation. According to The Worlds of the Federation, the fifth planet in the system was the homeworld of the Tellarite race.
61 Cygni (Tellar): This was a binary star system. Teller A was a K-class star with a magnitude of +5, which was the same brightness as Sol. Teller B was a K-class star. There was an inhabited planet, Tellar Prime, in this system. The planet was the homeworld for the Tellarites, a warp-capable humanoid species. The system was located in Sector 007 (Tellar Sector) in the Alpha Quadrant. (pgs. 19, 36)