As a writer, you’ve probably asked a friend or colleague to look over a blog post before it went live. Newsrooms and brands alike often have many editorial procedures in place to assure that work gets another set of eyes before it is published. Collaborative editing is simply the process of working with one or more people who review your work and make suggestions or changes. In the age of the typewriter, this was done with a stack of papers and a red pen, but nowadays, new tools emerge regularly. Here’s a look at three of them (and a bit of a teary goodbye to a fourth).