Configs refer to the configuration files which are used by the game to quickly change game settings, such as graphics and gameplay options. Many configs are designed to improve game performance through lowering graphics settings, as well as providing extra functionality through the use of other client commands, such as viewmodel tweaks and network settings.
FPS configs strive to lower game graphics as much as possible in order to increase the framerate (FPS) of the game. Popular graphics configs include Comanglia's and mastercomfig, while configs such as m0reframes and Chris's config have been used in the past.
CFG.TF - is a config generator which includes well known and updated graphics configs. You can automatically install custom configs such as offline rocket jumping config, automatically record games, custom files such as remove bullet-hole dust, viewmodel settings, crosshair switcher, damage indicators, network settings, custom binds, HUDs and a lot of other things.
mastercomfig - The latest config available, with a focus on optimizing the game with a modern approach. Gets new updates frequently and has many customization options. Along with mastercomfig comes the mm_override.cfg file, which changes some settings to comply with the commands that are changed in Competitive matches.
Comanglia's FPS Config - Historically the go-to config for most competitive TF2 players who need more frames. It's considered by many to be one of the most effective configs currently available.
Rhapsody's Performance Config - An updated version of Chris' dx9frames config created by RhapsodySL. Gives higher frames than Chris' version did and also has some extra features such as in-game config setting managing, among other things.
Chris' Configurations - FPS configs maintained by Chris until 2012. This config used to be the most popular and is still used by a number of TF2 competitive players. Chris' Configs come in several different versions, the most popular of which is the "maxframes config", which gives the maximum framerate possible while at the same time reducing the quality of the textures and the overall look of TF2. Alternatively, players can go for the "Highframes config", which makes TF2 look a little better compared to "Maxframes" but at the expense of not getting the maximum possible framerate.
m0re FPS Configurations - m0re FPS Configurations is the FPS config which pales in comparison to Chris' Configs due to performance but is a healthy alternative to Chris' Configs.
Transparent Viewmodels - Makes your weapon viewmodel's transparent
Null-Cancelling Script - This script prevents you from pressing two opposing directions, which causes you to stop moving.
Improved Crouch Jump Script - a simple script that lets you press space once to jump then keep holding space to crouch.
Comp Medic Config - A fleshed out Medic Config with the essentials for playing Medic at a higher level.
Helpful Spy Scripts by Stabby Stabby - A set of scripts created by Competitive Spy Stabby Stabby for spy.