A long but very interesting piece starting all the way from early typing on machines to more modern input systems. It's very focused on Apple machines towards the end, but there are good design lessons to draw from the long perspective.

Let's not forget where we're coming from and why window managers tend to be merged with display server. It removes some complexity and some latency.

A long article which seems to be a good reference document on the Linux input stack. There's a lot to cover as it's quite fragmented.