It features procedurally generated environments, including planets (with flora & fauna), star systems, and galaxies for the player to explore. Also, like Frontier and Evochron Mercenary, the game features a seamless transition between the surface of a planet and space.
Development of No Man's Sky started in 2012, under the codename "Skyscraper." Heavy inspiration for the game was drawn from the Golden Age of Science Fiction, i.e. authors such as Isaac Asimov, Robert A. Heinlein and Frederik Pohl, and notably, the illustrator Chris Foss.
Hello Games has remained intentionally vague in regards to the gameplay loop in No Man's Sky, but have said that the game will not be a primarily ambient experience, like Proteus or Dear Esther. Players will be free to explore a procedurally generated universe in first-person, via their own spacecraft. The Atlas, a translucent diamond-shaped prism with a red bubble inside, is the only current indication towards any in-game fiction or overarching objective.
All No Man's Sky players share the same procedurally generated universe, with all of its content being generated under one seed, and the locations and generated content being kept consistent. However, when a player discovers a new planet or species they will have the option of naming it, thus changing its official designation.
Each new player will start out on a previously-undiscovered planet on the rim of the galaxy. Hello Games have set the expectation that a central goal of the game will be to reach the center of the universe. The game difficulty will increase as players progress towards it, with more malevolent robots going after them, and more hostile planets being generated along the way.
Gameplay is known to include space and ground based combat, open world exploration, and survival-based scenarios. Resources (or RESOZU in game) acquired in-game via exploration, cataloging wildlife, combat or trading with aliens will serve as the player's currency. They will be able to spend them on upgrades for the suit (to provide greater resistance to toxic, radioactive and underwater environments), tools for resource acquisition, and weapons for on-foot combat. Ships will also be purchasable, with add-ons such as scientific equipment and propulsion upgrades. Crafting will be another part of the game, with the player having to acquire recipes before creating certain items.
Being defeated by enemies will lose players their accumulated upgrades, however this is not a game failure state. Players defeated in space, for instance, will be left in a escape pod with their bank balance, and will have to reacquire a spaceship.
No Man's Sky is not an MMO. However, online interaction will include an asynchronous pooling of the players' discoveries into a central database, as they collectively catalog the universe. Social features have been confirmed, such as an in-game chat capability, as well as some currently undefined abilities for players to help each other remotely.
Encounters between players will be possible, but interaction will be limited. Furthermore, discovering other players will be highly unlikely, due to the magnitude of the play area.
All musical accompaniment to preview gameplay has been by Sheffield based, post-rock act 65daysofstatic. Most predominantly, the track Debutante from We Were Exploding Anyway. Sean Murray of Hello Games says that the act will be producing the soundtrack for the game, and will also releasing a No Man's Sky album.