Resource list
A Resource list (.res
file) accompanies a map. When the map is running, it directs the server to push arbitrary files to connecting clients.
While it is generally preferable to achieve this by using BSPZIP to embed the files into the map itself, there are occasional situations where only loose files and a .res will work.

\maps
folder with the same name as the associated BSP.Example
Resources { "materials/vdc/some_material.vmt" "file" "materials/vdc/some_material.vtf" "file" }

- To do: What data types are there beside
file
? - To do: Can a .res be safely BSPZIPped?
VGUI Resource Files
Some resource files can be found in your /resource folder. Most of them are for VGUI.