Google Wave is a tool for communication and collaboration on the web, launching in the second half of 2009. Google announced that they would discontinue new development on Google wave in August 2010 and that waves would no longer be visible after April 30, 2012.
In Google Wave, users create and invite other people to “waves.” Everyone on a wave can use richly formatted text, photos, gadgets, and even feeds from other sources on the web. They can insert a reply or edit the wave directly. It’s concurrent rich-text editing, where you see what other users on the wave are typing in real-time. That means Google Wave is just as well suited for quick messages as for persistent content—it allows for both collaboration and communication. You can also use “playback” to rewind the wave to see how it evolved.