This document discusses how to build online learning communities using social networks like Twitter. It explains that through following others, their posts can lead you to more resources like blogs, videos, and other people to follow. By reciprocating and sharing your own knowledge, the online community grows through this positive cycle of contribution and accumulation of knowledge from many individuals. The document encourages educators to sign up for services like Classroom 2.0 and Twitter, create profiles with their areas of expertise, and begin following and engaging with others to start developing their own online learning community.