In 2009, Twitter, the social-networking platform that allows
users to post content up to 140 characters in length, was gaining
momentum. Users produced nearly 100 million tweets per quarter
the year before—a 250 percent increase from 2007. During this
time, Anderson began connecting with educators Shelly Terrell, a
foreign language teacher working in Germany, and Tom Whitby,
a retired English teacher turned education professor at St. Joseph’s
College in New York. These three Twitter pioneers saw the education
conversation evolving on Twitter and wanted to organize
it for other educators to join. Terrell suggested using a hashtag
symbol, a Twitter feature that when prefixed to a word flags your
post so any Twitter user can read it by searching that same word.