Object Lessons is a series of short, beautifully designed books about the hidden lives of ordinary things. Hashtags can silence as well as shout. They originate in the quiet of the archive and the breathless suspense of the control room, and find voice in the roar of rallies in the streets. The #hashtag is a composite creation, with two separate but related design histories: one involving the crosshatch symbol and one about the choice of letters after it. Celebration and criticism of hashtag activism rarely address the hashtag as an object or try to locate its place in the history of writing for machines. Although hashtags tend to be associated with Silicon Valley invention myths or celebrity power users, the story of the hashtag is much longer and more surprising, speaking to how we think about naming, identity, and being human in a non-human world. Object Lessons is published in partnership with an essay series in .