What even is a source port anyway?
A source port is a port of the source code for the Quake engine (originally only available for DOS platforms) to other platforms. Often times, these new source code ports will upgrade the capabilities of the game engine, granting mod developers the chance to expand the original game's content and compatibility to what was originally intended.
In more general terms, a Source Port is just what us people in these retro game communities call a new engine derived from the original.
Since the old engines no longer run on modern systems / weren't ported by the developers to consoles / etc, you'll need to have one of these bad boys to play Quake in all of it's glory on modern hardware.
Right so I need a...