You mean the `Include` directive, right? Not "load"...but I guess that's just shorthand for the concept.

So you split your main ~/.ssh/config file into smaller, reusable files stored in a subdirectory like ~/.ssh/config.d/. The main config file then "includes" (loads) these modular files automatically. So for instance, you might have:

~/.ssh/config.d/10-general.conf

~/.ssh/config.d/20-work.conf

~/.ssh/config.d/30-github.conf

Can confirm this works great in teams or on multi-host setups, as it keeps things organized without cluttering a single massive config file and it works across tools like ssh, scp, rsync, etc.

It also makes automation easier. I have a script auto adding vagrant VMs under known names when working on a project with vagrant. And had to go at great lengths to avoid nuking the main config file.

And same for for Emacs: it's much easier to vibe code some changes (don't know ELisp that well). And then when knowledge of the language matures I can look at fixes and at least know what was the idea behind them.