An online spreadsheet is a spreadsheet document edited through a web-based application that allow multiple persons to edit and share it with the world. With the advent of web 2.0 technologies such as Ajax circa 2005, a new generation of online spreadsheets has emerged. Equipped with a rich Internet application user experience, the best web based online spreadsheets have many of the features seen in desktop spreadsheet applications. Some of them have strong multi-user collaboration features. Some of them offer real time updates from remote sources such as stock prices and currency exchange rates. Online applications are now becoming known as "Cloud Apps".