Google on Wednesday launched Sidewiki, a Web annotation tool that serves as a comment forum for Web pages. Sidewiki ranks entries according to their relevance, as determined by Google’s own algorithm.

Would researchers scrawl notes, critiques and comments across online research papers if software made the annotation easy for them? Dan Whaley, founder of the non-profit organization Hypothes.is, ...

Earlier this year, a group of climate scientists were outraged about a Wall Street Journal editorial. In an earlier era, they might have written a letter to the editor, or meekly submitted their ...