"... the practice of maintaining miscellanies and commonplace books and exchanging texts with others served as a form of self-definition: which poems or aphorisms people chose to copy into their books or to pass on to their correspondents said a lot about them, and the book as a whole was an expression of its owner's character and personality. Poeple would sometimes lend their commonplace books or miscellanies to their friends, who could then page through the entries and copy anything of interest into their own books. Like Internet users setting up blogs or social-media profiles for the first time compilers of such books seem to have relished the opportunities their newfound literacy gave them for projecting a particular image of themselves to their peers."
Tom Standage, Social Media: The First 2000 Years