> It's hard to directly compare things to 20 years ago; "real-time collaborative editing of a document (with automatic saving and unlimited undo) over a video c

> It's hard to directly compare things to 20 years ago; "real-time collaborative editing of a document (with automatic saving and unlimited undo) over a video call" wasn't done because we lacked the internet speeds and computing power to make that viable, not because UI paradigms improved. But that's not true. 2003, 20 years ago, happens to mark the launch of both the first modern collaborative real-time editors (SubEthaEdit and MoonEdit) and a major video calling service (iChat AV). Sure, hardware progress since then has helped. Video calling got much better due to internet, camera, and codec improvements, along with webcams becoming a ubiquitous component of computers rather than an external addon. Collaborative editing really took off once it started to work in web browsers, originally with EtherPad, but more importantly with Google Docs. That's partly due to the UI paradigm of the URL, but the ability for collaborative editing to work in web browsers can also ascribed to faster CPUs, as well as browsers getting more efficient (which is not hardware but also not a matter of UI paradigms). Still. Ignoring the calling part (which really isn't essential, IMO), collaborative editing isn't necessarily very resource intensive (depending on the algorithm). The technical conditions for it to work were satisfied as soon as Internet access became a ubiquitous feature of computers in the late 90s. Yet it wasn't until 2010, when Google Docs gained collaborative editing, that it even started to take off. I'd say that's definitely an example of UI paradigms improving over time. By the way, a form of collaborative editing was shown off in 1968 in the Mother of All Demos, with video calling! It used analog video.