Google Wave

Google Wave is an internet application made by Google. Google describes Wave as an application which "lets you communicate and collaborate in real time". This means that Wave can be used for several people to edit a document at the same time, or for a group discussion. Waves can be used in a similar way to a forum, or just for emails and instant messaging between two or more people.
To use Google Wave in some browsers like Internet Explorer, you have to install Google Chrome Frame. This makes Internet explorer behave like Google Chrome on the Wave website. This is needed because Internet Explorer does not have enough features for Wave to work: it does not have full HTML5 support.
Google Wave was discontinued in 2010. It has been open sourced as Apache Wave.
(source: https://simple.wikipedia.org/wiki/Google_Wave)