Gameplay begins with the player selecting or joining a world with specific settings, such as the number of asteroids and the available starting equipment. Once in-game, the player is given control of a single astronaut, which is referred to as a Space Engineer. The player can then build a station, large ship, or small ship. Construction begins by choosing one of the three options and placing a block, which is used as the starting point for the rest of the structure. Blocks may be structural, functional, interactive, or aesthetic, and may fall into more than one category. Blocks also take up varying amounts of space. In addition to placing blocks, the player can also use tools and weapons. Most blocks can be damaged and deformed through collisions or by weapon impacts.