The Elder Scrolls V Skyrim
Version replace color filter with custom external shaders, fix some game bugs/crashes and applies memory manager for textures (ENBoost), allow to tweak many parameters of objects, add lot of new effects, etc.

Modification do not have graphic preset, by default it's ugly unconfigured (unless specified in description of version), so you need to download such presets made by users, feel free to visit my forum or Nexus site for them. Also you can edit parameters to your own taste inside integrated editor (display it by pressing SHIFT and ENTER keys together, by default).

Effects and features includes (but not complete list): memory usage reducing and crash preventing, color filters, programmable post process shaders and camera effects, bloom, subsurface scattering, depth of field, indirect lighting and ambient occlusion, lens reflections, detailed shadows and improved quality of original shadows, image based lighting, time of the day and weather dependent parameters, reflections, sun rays, fire and particle controls, soft particles and lights from particles, fps limiter, fps measure, screenshot capture.
Highly recommended TES Skyrim bug fix of game objects like fire, water particles, doors, vegetables, candles, etc is available here
Version 0.088 is the first version released for the game, include just bugs and performance fixes of the game.
Version 0.102 Tatsudoshi is New Year 2012 release, the same as previous versions, it use fake "ENB" video adapter to fix game bugs like transparent water and invisible fire (not actual now, but users of Radeon 2xxx/3xxx still have these issues). Not recommended, because it's very slow.
Version 0.103 Injector first version with special ENBInjector tool which allow to run mod while some incompatible software used (Afterburner, XFire, etc) or for Optimus laptops. Not recommended, because it's very slow.
Version 0.108 TrueHDR is very fast and simplified without most effects.
Version 0.119 last non deffered which completely support hardware antialiasing (msaa), but at cost of performance and quality. Latest versions support antialiasing, but some effects do not work.
Version 0.132 just a progress, requested to keep on the site for compatibility with some presets.
Version 0.168 just a progress, requested to keep on the site for compatibility with some presets.
Version 12.12.12 is performance optimized, but it's very old.
Version 13.7.13 is the last which optimized for old videocards of DirectX10 generation like GeForce 8xxx/9xxx/2xx and Radeon 2xxx/3xxx/4xxx, so each version after that developed corresponding to modern DX11 generation of videocards which have much faster arithmetics. Some effects may run slower for old cards, but faster for new. Sorry, but i can't make two versions, so after purchasing modern videocard everything changed accordingly.
Version 0.192 and newer include ENBoost patch (available for some other games too) which reduce memry usage of the game and as result fewer CTDs (crashes) and you may install much more modifications.
Version 0.226 support helper plugin which allow to use weather system and time without problems with game scripting.
Version 0.290 added support of SDK to control parameters.
Version 0.303 added new ENBoost 6.0 functionality for higher stability at cost of performance.
Version 0.304 added localization support.
Version 0.305 added dawn and dusk times of the day, which can be disabled for compatibility with old presets.
Version 0.404 improved performance of ENBoost.
Version 0.472 added support of normal maps for grass via atlas.
All newest versions are compatible with each over and i recommed to use latest.

Hardware antialiasing (msaa) supported in versions 0.119 and lower for all effects, all other version use deffered rendering which do not support aa. But in latest mods (starting from v0.180 if i remember, inclufing v13.7.13) you may enable antialiasing, many effects will turn off automatically then, but in general colors will be the same.
Presets are compatible with other versions of the mod with minor changes. For example 0.088-0.119 versions may use the same preset, 0.119-0.132 too, 0.132-0.168, etc.

v0.479
v0.434
v0.292
v0.262
v0.236
v0.221
v13.7.13
v0.168
v0.132
v121212
v0.119
v0.117 beta
v0.108 TrueHDR
v0.103 Injector
v0.102 Tatsudoshi