I went Gameservers.com. Don't think they mentioned rcon.
i should be more descriptive
my original description is wrong, srcds isn't an rcon program, it's what starts the server and gives you a console. you can perform commands server-side with the console provided by srcds. rcon (remote console) is what server administrators can use to perform server-side console commands in their local console.
rcon passwords can be set using the srcds console (or server.cfg) with rcon_password "pass name here"
administrators playing tf2 can use rcon by typing "rcon_password 'whatever you set it to';" in their local console.
if you buy a server hoster, like crident or nodecraft, a console will be provided to you.
using rcon is fairly simple, just type "rcon <whatever command>" in your local console
clients that don't have the rcon password will only be able to use client-side commands, i.e "viewmodel_fov 70"
clients with the rcon password can run server-side commands, i.e "rcon sv_cheats 1"