Twitter used the internal name “twttr” during its earliest development in 2006.
The name was chosen for the prototype created inside Odeo, a San Francisco podcast company. It followed a contemporary internet naming style that removed vowels from words, while also suggesting short text messages and bird sounds. The service’s first post used the same spelling.
As the project moved beyond internal testing, the name became “Twitter.” The full word was more recognizable to users and better suited to a public consumer service. The company retained the short “twttr” spelling in early historical references and in the text of its first post.
The name is sometimes confused with the later “Twitter” brand or with the service’s original 140-character format. The shortened version refers specifically to the prototype and early development period, not to a separate social network.