Now I see

[Protoford]

Been playing OpenTTD for nearly ten years and am only now seeing groups in the docs. I only looked for it because some viewers of my stream criticized me for not using them. Is this carried over from the original TT Deluxe? I don't remember. Glad to find it in the wiki now, but it should be easier to find for codgers like me. Listed as a feature would be nice.

[Redirect Left]

I don't think it was part of the original game.

There's quite a lot of features in OpenTTD that are either fairly hidden, or otherwise not really documented well (whomever updates the wiki tries their best, but its often outdated, usually not to a big degree).
A lot of clicking on buttons to see what they do, as the game doesn't have a proper tutorial to teach you all these things, which to my knowledge is because it'd be annoying to make given the current codebase not really supporting such a thing.

[Protoford]

Ah, okay, and at the bottom of the page it says added in 2007 for version 0.6.0