Still not sure? well here is a video with a comparison of ENB and Default graphics, just as an example
This is a shader add on that has several different shader effects built in . Things like Depth-of-field, Motion blur, bloom, SSAO, color correction, Water, and more. the settings are VERY customizable, and can do things like add "photo-realism" in the right hands.
Several DX9 cores are available so you can use to try and match up to whatever random game you think it might work for. Sometimes it works, sometimes it does not ( directx support is key). but it can make a hell of a huge difference in any given older game ( between 2000 and 2008).
You can even use it with emulators! which in the case of older games, can smooth out pixels, and add a screen glow that was lost when the world retired tube based monitors .
And can even make Gamecube games look a little nicer using Dolphin
I'm bringing this up because I've been working on several ENB mods for a few years now , so when people say "WTF is an ENB mod, I can point them to this thread.
I'll get to MY mods later, I just wanted this to be sort of an introduction to it. if you have questions, then leave them here!!