Collaborative real-time editing

A collaborative editor is a form of collaborative software application that allows several people to edit a computer file using different computers, a practice called collaborative editing. There are two types of collaborative editing: real-time and non-real-time. In real-time collaborative editing (RTCE), users can edit the same file simultaneously, whereas in Non-real-time collaborative editing, the users do not edit the same file at the same time (similar to revision control systems). Collaborative real-time editors generally permit both the above modes of editing in any given instance.

The first instance of a collaborative real-time editor was demonstrated by Douglas Engelbart in 1968, in The Mother of All Demos. Widely available implementations of the concept took decades to appear.

Instant Update was released for the classic Mac OS in 1991 from ON Technology. Later, a version for Microsoft Windows was released as well, allowing real-time collaboration across these two operating systems. Instant Update relied on a work group server to coordinate documents updated in real time on multiple clients.

The Web 2.0 phenomenon has caused an explosion of interest in browser-based document editing tools. In particular, a product called Writely saw explosive user growth and was bought by Google in March 2006 (what become known as Google Docs and later renamed to Google Drive). It provided simultaneous edits on the entirety of a document, though changes from other users were only reflected after the client program polling the server (every half-minute or so). Another early web-based solution was JotSpotLive, in which line-by-line simultaneous editing was available in near-realtime. However, after Google's purchase of parent company JotSpot in November 2006, the site was closed. Google Sites was launched in February 2007 as a refactoring of JotSpot, but it lacks the multi-user real-time abilities of JotLive. The Synchroedit (rich text) and MobWrite (plain text) projects are two, more recent, open source attempts to fill the in gap real-time browser-based collaborative editing, though still unable to achieve true real-time performance, especially on a large scale architecture.

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