Google Docs' collaboration trick dates to 1989

A closer look

You hate collaborative document editing when your coworker's cursor deletes your sentence, but Clarence Ellis had to figure out how to make that nightmare work in 1989. While at Xerox PARC, Ellis spearheaded OfficeTalk, developing Operational Transformation—the exact underlying algorithmic magic that allows multiple people to type in a Google Doc simultaneously without the server bursting into flames. As the first Black man to earn a Ph.D. in Computer Science, he basically invented the modern concept of remote collaboration.