Creation Engine

The Creation Engine is an engine created by Bethesda Softworks for The Elder Scrolls V: Skyrim and Fallout 4.

Background
The Creation Engine is the successor to the Gamebryo game engine, and was launched to support The Elder Scrolls V: Skyrim. It retains much of the basic framework and has the same general feel, but adds numerous improvements over the older engine.
 * Draw distance is greater to give a more epic, open-world feel.
 * Multiple levels of detail on "distant" objects, such as cities on the horizon, allow a more immersive worldspace without sacrificing too much performance.
 * Shadows were greatly improved, allowing almost any object to cast a shadow in real-time and better lighting systems make the world seem more alive.
 * Animations used better blending to allow more complex actions to translate into the model, such as drawing a bow while strafing sideways and showing both actions simultaneously rather than one animation overriding the other.
 * The Radiant AI system, introduced in Oblivion, is expanded to allow non-player actors to have more diverse and believable day-to-day activities, while still being able to take part in quests and large-scale events.
 * The Radiant Story system was introduced with Skyrim to allow a more diverse array of dynamic quest elements and creation of on-the-fly quests, such as an innkeeper who might tell the player there's a local ogre who needs hunted, at which point the ogre is created by the engine rather than being created in advance by the quest team.
 * The user interface transitioned from the old XML frontends and hard-coded backends to a Shockwave Flash system that, while more complex to edit, allowed much greater flexibility for modders and numerous graphical effects previously unavailable gave the interface a much more polished look and feel.
 * The quest journal was extended to allow tracking multiple quests at once, or no quests at all, and included a "Miscellaneous" section for simple quests that would have been untracked in previous games. This allowed better tracking of minor side quests without cluttering the journal needlessly.
 * The combat system was significantly updated, with each hand free to use any type of shield, weapon or spell independently of the other hand, allowing a much more diverse range of character builds and more complex combat tactics.
 * A new perk system was added, giving each skill a tree of perks to further diversify character builds. Perks can range from simple +damage per rank to allowing special attacks with certain weapons to allowing stolen items to be sold to any merchant.
 * The crafting system was expanded on to allow more flexibility in crafting and enchanting equipment, although the spellcrafting system from previous Elder Scrolls games was non-existent in Skyrim.

Other titles
The recently released Fallout 4 utilizes an updated version of the Creation Engine, supporting better graphics capabilities and more features. Many of Skyrim's features will be removed or overhauled to fit the Fallout game world and SPECIAL skill system, but others will help the new game stand far ahead of Fallout 3 and Fallout: New Vegas.

The feature list will change as more information is released concerning Fallout 4, but a number of new or improved features are already known.
 * Increased texture resolution for more object detail.
 * Volumetric lighting gives more realism in scenes with stark lighting contrast, such as sunlight filtering through a row of columns and illuminating dust in the air between columns while leaving the dust behind the columns dark.
 * Physically-based rendering (PBR) shaders give a much more realistic look to the game's artwork and allow assets created under one lighting condition to look right under another more easily.
 * The new weapon and armor modification system allows far more creativity and diversity in player-made items.
 * A new settlement-creation system allows the player to build an entire town with fully customized building layouts and features, power grids, water supplies and more.
 * The character creation system has been redesigned into a point-and-click system rather than the old slider-based approach, and is intended to make getting that perfect face much easier.
 * The player character is now voiced, with a new camera view during conversations giving a more cinematic quality than previous games.
 * Conversations can be jumped out of at any time and dialogue choices have been simplified to a radial menu rather than scrolling through choices.
 * V.A.T.S. has been updated so time is still moving, but more slowly, to make V.A.T.S. combat more engaging than previous systems where time simply stopped while the player made their choices, while giving more precision than free-aim mode.
 * An iOS and Android app, Windows Phone app will allow accessing your in-game Pip-Boy wirelessly via smart phone.

Creation Kit
The Creation Kit is the official editor used to modify or create content for Skyrim, and is analogous to the Elder Scrolls Construction Set for Morrowind and Oblivion or the Garden of Eden Creation Kit for Fallouts 3 and New Vegas.

The majority of the functionality is unchanged, so modders using the old Construction Sets or G.E.C.K. will find the Creation Kit very familiar. As with every revision to a new game, however, there are a number of substantial changes to various subsystems of the editor to match Skyrim's new personality.

In addition, the scripting language was updated to the newer Papyrus language which has considerably more functionality than the scripting languages from older games.

The Creation Kit was released on February 7, 2012 and is currently at version 1.9.35.0.

Fallout 4 Creation Kit
An updated version of the Creation Kit for Fallout 4 has been publicly released for download for free on the Bethesda.net launcher following the closed beta. It can only be used if you have the PC version of the game. More information can be found on the Creation Kit wiki.