3D Systems, headquartered in Rock Hill, South Carolina, is a maker of rapid prototyping machines, notable for developing stereolithography and the STL file format.
Founded in 1986 by Chuck Hull, with the invention of the first stereolithography rapid prototyping system, 3D Systems is a global company that develops and sells systems, materials, and software for solid imaging. Its products are meant to make manufacturing processes more efficient, without requiring tooling. 3D Systems creates product concept models, precision and functional prototypes, master patterns for tooling, as well as production parts for direct digital manufacturing.
Their 3D printing, rapid prototyping and rapid manufacturing technologies use proprietary processes to fabricate physical objects using input from computer-aided design and manufacturing software, or 3D scanning and sculpting devices. 
3D Systems manufacture 3D printers, SLA systems and SLS systems.
- 3D modelers or printers take digital input from three-dimensional data and creates solid, three-dimensional parts through an additive, layer-by-layer process. 3D printing is used extensively by designers during concept development and early product design to accelerate the design process and improve the quality of the final product.
- Stereolithography or SLA systems convert proprietary materials and composites into solid cross-sections, layer by layer, until three-dimensional parts are built. An ultraviolet laser cures a liquid resin layer by layer to build highly accurate parts. SLA systems rapidly manufacture parts of different geometries at the same time and are designed to produce prototypes, patterns or end-use parts of versatile sizes and applications.
- Selective laser sintering or SLS systems use high-temperature laser to melt and fuse, or sinter, powdered plastics or metal into solid cross-sections, layer by layer, until three-dimensional parts are complete. SLS systems have integrated powder delivery/recycling, part-building and finishing capability as complete rapid manufacturing systems. The systems enable productive, direct rapid manufacturing of durable and tough three-dimensional parts that have versatile sizes and applications.
A number of industries, including automotive, aerospace, consumer appliance and electronics, toys and entertainment, and medical, use 3D printing, stereolithography and sintering. 
Facilities and employees
In 2006, the company consolidated its offices, operations, and research and development functions into a new global headquarters in Rock Hill, SC, USA. About half of the headquarters are R&D laboratories and an Rapid Manufacturing Center (RMC) with 3D Systems rapid prototyping, rapid manufacturing and 3D printing systems at work. 
3D Systems opened a training center, 3D Systems University, in partnership York Technical College to train prospective and existing customers. 
With customers in 80 countries, 3D Systems has 400 employees in offices around the world, including France, Germany, Italy, Switzerland, United Kingdom, China and Japan. The company has more than 359 U.S. and foreign patents. 
On 31 August 2009, 3D Systems acquired the key assets of Desktop Factory. On 12 May 2011, 3D Systems announced it acquired the Amsterdam-based 3D design company Freedom Of Creation (FOC).