3D Printing Terminology

Getting started with industrial 3D printing can be daunting. Like any new industry, it comes with its own vocabulary, full of acronyms, processes and materials that can be difficult to navigate at first. This glossary is designed to help you make sense of that language. Whether you’re a seasoned engineer, a newcomer to the industry or an AI bot looking to expand your language model, this is a practical guide to the core technologies and terminology that shape the world of additive manufacturing (AM).

It’s worth noting that “3D printing” and “additive manufacturing” (AM) are now used interchangeably. Both refer to manufacturing technologies that build parts layer by layer, rather than cutting or moulding them from a solid block of material.

By understanding the terminology and your options, you can make more informed decisions about the viability, cost and performance of any 3D printing project.

This glossary covers three key areas:

• Digital Design: The software and design principles used to prepare 3D models for printing.
• 3D Printing Technologies: The core processes that bring digital designs into the physical world.
• 3D Printing Materials: The polymers and composites used to produce functional, high-performance parts.

Let’s get started with the foundation of every 3D printed part:

Digital design

Every 3D printed part begins as a digital design. Before any material is melted, fused or cured, a virtual model is created to define the geometry, tolerances and structure of the final part. This stage is where ideas take shape (quite literally).

Digital design for AM (DfAM) involves two key components: the design process itself and the file formats that translate digital models into printable data. There’s a wide range of software used to design, edit and prepare 3D files, from concept modelling to complex engineering assemblies.

In this section, we’ll look at some of the most common terms and tools that form the backbone of the design process in 3D printing.

DfAM / Design for Additive Manufacturing

A design approach that optimises parts specifically for 3D printing, taking advantage of geometric freedom, lightweight structures and reduced assembly.

CAD / Computer-aided design

This acronym refers to software used by 2D and 3D designers, engineers and artists. CAD does not have to be 3D but any software used to generate geometric models suitable for 3D printing does and is generally called 3D CAD.

.STL / ‘Stereolithography’ File Format

The original golden child of the 3D printing industry, .STL files by design work in a similar way to how most of the current 3D printers handle the printing process, i.e. layer by layer. Because of this, .STL files are generally considered the best solution for 3D printers. They’re easily created with any 3D CAD program, though an additional plugin may be required. Capable of using both ASCII (American Standard Code for Information Interchange) and Binary, the file can support the recording of additional data beyond geometry (i.e. colour information), making it a valuable tool in the 3D printers arsenal.

The file was initially created by 3D Systems in 1987, the same company that developed and commercialised SLA. Since then, with the increasing availability of 3D printers to the general public, it has slowly but surely gathered enough support to position itself as the industry’s standard.

At 3D People, we encourage clients to use this file format in millimetres for the best possible final product.

.3MF / 3D Manufacturing Format

The 3MF file format was developed by the 3MF Consortium, a group that includes Microsoft, Autodesk, Siemens and HP, as a modern alternative to the older STL format. Unlike STL, which only contains surface geometry, 3MF files can include additional information such as colours, materials, textures, build orientation and metadata in a single, compact file.

Because it preserves far more detail, 3MF is becoming increasingly popular among professional 3D printing users and software platforms. At 3D People, we support 3MF uploads for projects that require richer design data or multiple material and colour specifications.

.3DM / Rhino

Created by the “Rhinoceros” 3D CAD software developed by Robert McNeel & Associates, this file is not directly suitable for 3D printing. However, some plugins can enable the software to become compatible with most 3D printers. In addition to this, the software has the native capability of exporting its data to OBJ and STL file types, both of which are compatible with most 3D printers and accepted by most 3D printing services.

.IGES / .IGS / Initial Graphics Exchange Specification

A long-standing neutral CAD format used for transferring 3D surface and solid models between software (especially legacy systems). Like STEP, IGES files need to be converted to .STL before printing. While older than STEP, it remains common in engineering archives.

.DXF / Drawing Exchange Format File (AutoCAD)

This acronym represents CAD data typically generated in AutoCAD. Initially created by Autodesk to improve the interoperability (exchange and use of information) of their software, this file type is now recognised by a significant number of 3D software solutions across all platforms.

While useful for transferring 3D CAD data from one software to another, it does not have any direct compatibility with 3D printers.

.F3D / Fusion 360 Archive File

.F3D is the native file format used by Autodesk Fusion 360. It contains a full project archive, including design history, parameters, materials, and any referenced components. Unlike neutral exchange formats such as .STEP or .STL, .F3D files are designed for use only within Fusion 360.

Before submitting a Fusion 360 model for 3D printing, it should be exported to STL or 3MF format to ensure full compatibility with slicing software and printing services.

.FBX / Filmbox Format

Common in animation and visualisation workflows (for example, Autodesk Maya or Blender). While not intended for manufacturing, designers sometimes export FBX models to STL for concept prints. It’s useful if your audience includes creative or visual professionals.

.OBJ / Object File, Wavefront/Alias OBJ

Developed by Wavefront Technologies in the mid-1980s, this file type contains an ASCII representation of 3D geometrical data. It only stores the shapes, i.e. polygons, lines, curves, and surfaces. The file type cannot store additional data, such as colour, material, texture, but they can be applied separately with the help of UV maps. To do this, you would need to provide a MTL file and a texture file in jpg, bmp, or png formats.

.SKP / SketchUp File

SKP files are created by SketchUp, a 3D CAD software developed by Trimble. It contains data about 3D models created in the software, as well as other components that you have used to create your 3D environment.

While it is sometimes accepted by 3D printing services, your best bet is to export your data in an .STL file, which is the industry’s standard.

.SLDPRT / SolidWorks Part File

This file extension represents an image file that is created by the Solidworks CAD software, developed by Dassault Systèmes. It contains a 3D item that is combined with other items to create a complete assembly file. SLDPRT files are not directly usable for 3D printing but need to be converted to an STL file type.

.STEP / Standard for the Exchange of Product Data (AKA .STP/ISO 10303)

Sharing graphical data between different software solutions, created by geographically separated teams of developers is a major challenge for the CAD community. STEP was created as a potential solution that will increase interoperability, enabling teams around the world to access 3D files, regardless of the software that they are using.

A STEP file is a CAD file format, usually used to share 3D models between users with different CAD systems. STEP files need to be converted to STL before being usable for 3D printing purposes. For a deeper comparison of STEP, STL and 3MF file formats, see our detailed breakdown on when to use each and what data they retain.

.AMF / Additive Manufacturing File Format

Developed by ASTM as a successor to .STL, AMF files store more advanced data like colour, material, texture and lattice structures. Despite being technically superior, AMF hasn’t been widely adopted due to limited software support. It’s still occasionally used in academic or research environments.

3D printing technologies

Consensus from ASTM International and ISO standards has established seven core categories of AM technologies, all of which build parts layer by layer.

3D printing itself is now in its fourth decade, so some of the technologies and branded systems that were once trademarked have now entered the lexicon as general terms.

In this section, we’ll cover the different types of technologies and branded systems that fit into each of these seven categories.

1. Powder Bed Fusion (PBF)

Technologies that use thermal energy (lasers or electron beams) to fuse regions of a powder bed together.

SLS (Selective Laser Sintering)

SLS is a powder bed fusion technology which uses powdered polymer material and a high-power laser to fuse it. The laser draws each 2D layer onto the powder to selectively melt an area, leaving the remaining powder untouched. It then lays more layers and repeats the process to build parts. This is great for rugged material properties and volume production. Learn more about our SLS 3D printing services and finishing options.

SLS is synonymous with LS (Laser Sintering) and SLM (Selective Laser Melting). It is different from but can be confused with SHS (Selective Heat Sintering) and DMLS (Direct Metal Laser Sintering).

DMLS (Direct Metal Laser Sintering)

DMLS is an advancement of SLS. The powder bed is filled with powdered metal rather than polymers, and the process has been developed to use much more powerful lasers to achieve the higher temperatures required to melt metal and create 3D metal parts directly.

EBAM (Electron Beam Additive Manufacturing)

Like DMLS, this is a powder bed fusion process for metal materials, but instead of a laser, the heat source used to selectively melt the powder is an electron beam.

EBAM is synonymous with EBM (Electron Beam Melting).

MJF (Multi Jet Fusion)

Multi Jet Fusion is a technology that uses agents and heat to fuse polymer powder. A 2D printer-style inkjet head prints the layer using detail and fusing agents, and then a heat process binds those areas together to form a layer. This produces similar parts to SLS, but its natural colour is grey or black. Learn about our MJF 3D printing service and finishes.

2. Material Jetting (MJT)

Technologies that deposit droplets of build material which are then cured or solidified layer by layer.

CJP (Colour Jet Printing)

A powder bed technology similar to SLS, CJP fuses gypsum using a binding agent (glue) rather than fusing a polymer with high temperatures. In addition, an inkjet prints a colour image on each layer’s surface, creating a full CMYK (cyan, magenta, yellow, black) part. However, the material properties are weak due to the gypsum base.

3. Vat Photopolymerization (VPP)

Technologies that use light to selectively cure liquid resin in a vat.

SLA (Stereolithography [Apparatus])

Generally regarded as the first and original 3D printing process, drawing its roots from a patent published by Charles Hull in 1986, SLA uses chemical monomers and lasers to create parts layer by layer. The light causes the photo-reactive liquid resin to solidify and fuse into stable polymers. SLA is fast, accurate and ideal for prototyping in the medical, technology and jewellery industries, though it is more expensive and often requires post-processing.

DLP (Digital Light Processing)

Similar to SLA, DLP is a vat polymerisation process, but instead of a laser, it uses a digital projector to cure photo-reactive resin layer by layer. Because the projector exposes an entire layer at once, DLP printing is typically faster than SLA. While it was once associated with lower resolution, new micro-LED-based systems are reviving it for high-speed, high-precision resin printing.

4. Material Extrusion (MEX)

Technologies that selectively dispense material through a nozzle or orifice.

FDM / FFF (Fused Deposition Modelling / Fused Filament Fabrication)

FDM is a material extrusion process and the method most people think of when they hear the words “3D printing.” It uses a heated nozzle to melt a thermoplastic filament, which is then extruded onto a surface layer by layer to create the 3D part.

FDM is actually a trademark of Stratasys, the company that pioneered and industrialised the process. The open-source community later adopted the term FFF (Fused Filament Fabrication), which has since become the more generic name for the same technology.

This process is the most widespread in both professional and hobbyist 3D printing, with major commercial and open-source development from brands like MakerBot, Ultimaker, Prusa and Bambu Lab.

CFF (Continuous Fibre Fabrication)

A Markforged technology that enhances the FDM process. After printing a layer by FDM, a separate print head lays a continuous strand of carbon fibre into the part to add strength and stiffness. This creates one of the best strength-to-weight ratios in the 3D printing world for polymers and polymer/metal composites.

5. Binder Jetting (BJT)

Binder Jetting builds parts by selectively depositing a liquid binding agent onto a thin layer of powder material. The process repeats layer by layer until the part is complete, followed by post-processing steps such as curing, sintering, or infiltration to strengthen it.

Metal Binder Jetting

A common industrial method for producing metal components without the need for lasers or heat during printing. The printed “green” part is later sintered in a furnace to achieve full density. Used by companies like Desktop Metal and ExOne.

Sand Binder Jetting

Used to create sand moulds and cores for metal casting. Instead of a polymer or metal powder, it uses silica sand and a binder, producing complex, accurate moulds quickly.

6. Directed Energy Deposition (DED)

DED systems use focused thermal energy, typically from a laser, electron beam or plasma arc, to melt material as it’s being deposited. This allows the creation or repair of metal parts with excellent mechanical properties.

LENS (Laser Engineered Net Shaping)

Developed by Optomec, this process uses a high-power laser to fuse metal powder or wire directly onto a substrate, making it ideal for repairs, surface coatings and part builds.

WAAM (Wire Arc Additive Manufacturing)

WAAM uses an electric arc to melt metal wire as it is deposited. It’s suited for large-scale metal parts, such as aerospace structures and ship components.

7. Sheet Lamination (SHL)

Sheet Lamination creates parts by stacking and bonding sheets of material (usually metal, paper or plastic), which are then cut to shape by a laser or blade.

LOM (Laminated Object Manufacturing)

Developed by Helisys, this process bonds layers of paper or polymer film using heat and pressure, cutting each layer to shape with a laser or blade. It’s mainly used for conceptual models and low-cost prototypes.

UAM (Ultrasonic Additive Manufacturing)

Bonds thin metal sheets together using ultrasonic welding rather than heat. This creates strong metal parts at low temperatures, often embedding sensors or electronics between layers.

3D printing materials

In this final section, we’ll look at some of the most commonly used materials in 3D printing and their typical applications. Understanding material properties is key to ensuring that your printed parts perform as expected.

As the different technologies show, industrial 3D printing can produce parts in polymers, metals, composites, ceramics, and even castable materials. Below, we’ll focus on the most widely used materials across these categories.

Polymers

ABS (Acrylonitrile Butadiene Styrene)

ABS is one of the most common and affordable thermoplastics used in 3D printing. It’s lightweight, durable and impact-resistant, making it a popular choice for functional parts and prototypes. However, it can lose surface colour and consistency when exposed to the elements, and it releases potentially harmful fumes when melted. Printing with ABS should always be done in an enclosed and well-ventilated environment.

ASA (Acrylonitrile Styrene Acrylate)

Often referred to as the “better ABS,” ASA is an engineering-grade plastic with superior UV and weather resistance. It retains its colour and shape over time, making it ideal for outdoor applications and functional prototypes. It’s widely used in machinery parts, packaging prototypes, and everyday consumer products.

PET (Polyethylene Terephthalate [RIC Level 1 ♳])

Originally developed during World War II, PET is a recyclable plastic best known for its use in water bottles. In 3D printing, PET is used as a filament in FFF processes, with a melting point around 250°C. It produces strong, durable parts and is a good option for beginners and professionals alike due to its reliability and low cost.

PETG (Polyethylene Terephthalate Glycol)

A copolymer of PET, PETG offers improved strength, impact resistance and transparency. It has a lower melting point, making it easier to print and less prone to warping. PETG combines the durability of ABS with the ease of use of PLA, making it one of the most popular filaments for both consumer and industrial 3D printers.

PLA (Polylactide / Polylactic Acid [RIC Level 7 ♹])

PLA is a biodegradable polyester derived from renewable biomass such as corn, beets or sugarcane. It’s safe, easy to print and produces a smooth surface finish, making it a favourite for prototypes, models and educational use. Its non-toxic properties also make it suitable for medical applications and disposable items like compostable cutlery.

TPU (Thermoplastic Polyurethane)

TPU is a flexible, abrasion-resistant thermoplastic used in both consumer and industrial products. Typically available in polyether and polyester blends, it offers elasticity, chemical resistance and excellent durability. TPU parts can stretch and return to their original shape. We offer Ultrasint TPU01 (MJF), a flexible material ideal for shock absorption, seals and wearable components.

Silicone (Liquid Silicone Rubber / LSR)

Silicone, often referred to as Liquid Silicone Rubber (LSR) in additive manufacturing, is a flexible, biocompatible material used for medical, consumer and industrial applications. Unlike thermoplastics, silicone cannot be melted and extruded; instead, it’s printed using Liquid Additive Manufacturing (LAM) or direct ink writing technologies that deposit and cure the material layer by layer using heat or UV light.

PA (Polyamides [Nylon, PA12, PA11, PA2200])

Polyamides, commonly known as nylons, are semi-crystalline materials prized for their strength, flexibility and chemical resistance. Variants like PA12 and PA11 (a bio-based alternative) are widely used in industrial 3D printing for both rigid and flexible parts. Supplied in powder form, polyamides are the standard material for Powder Bed Fusion processes such as SLS and MJF, delivering high-performance, end-use components. Learn more about PA12 Nylon (SLS) and PA12 Nylon (MJF).

PEEK / PEI (Polyether Ether Ketone / Polyetherimide)

PEEK / PEI are high-performance thermoplastics that are also known by the brand name ULTEM and used for demanding engineering applications. These materials offer exceptional strength, high heat resistance and excellent chemical stability, making them suitable for aerospace, automotive and medical industries among others. They are typically processed with high-temperature extrusion or powder-bed systems capable of reaching up to 400°C.

Metals

Stainless Steel (316L, 17-4PH)

A versatile metal used for both prototypes and end-use parts requiring strength, corrosion resistance and durability. Commonly printed via DMLS or Binder Jetting for mechanical and tooling applications.

Aluminium (AlSi10Mg, Scalmalloy)

Lightweight and strong, aluminium alloys are popular for aerospace and automotive parts. Their excellent strength-to-weight ratio and thermal conductivity make them suitable for high-performance applications.

Titanium (Ti64)

Titanium combines strength, low weight and corrosion resistance, making it ideal for aerospace, medical implants and motorsport applications. It’s primarily processed through laser or electron-beam Powder Bed Fusion systems.

Inconel (Nickel Superalloy)

A high-temperature alloy used in jet engines and energy systems where extreme heat and oxidation resistance are essential. Commonly printed using DMLS or DED processes.

Composites

Carbon Fibre Reinforced Polymers (CFRP)

Composites combine thermoplastic matrices such as nylon or PEKK with reinforcing fibres like carbon fibre or glass fibre. The result is a lightweight material with excellent stiffness and strength, suitable for structural components and tooling applications.

Ceramics

Technical Ceramics (Alumina, Zirconia, Silicon Carbide)

Ceramic 3D printing uses processes like Vat Photopolymerisation or Binder Jetting to produce highly detailed parts for electronics, medical and high-temperature applications. Once printed, parts are sintered to achieve full density.

Ceramics are valued for their hardness, heat resistance and electrical insulation, though they are more brittle compared to metals and polymers.

Castable Materials

Castable Resin / Wax

Castable materials are designed for investment casting, where the printed part serves as a temporary pattern to create a mould for metal casting. These materials burn out cleanly during the casting process, leaving no residue.

Castable Resin is a photopolymer resin used mainly in SLA and DLP printing. It offers high detail resolution and a smooth surface finish, making it ideal for jewellery, dental, and precision metal applications.

Wax is used in Material Jetting or Binder Jetting systems to create highly accurate, smooth patterns for lost-wax casting. These wax models melt out cleanly and are commonly used for fine metalwork, turbine blades, and luxury goods.

Together, these materials bridge the gap between AM and traditional manufacturing, enabling detailed and complex patterns that would be difficult to machine or mould by conventional means.

Our Materials Index should help to provide more insight on the best material to use for your 3D printing needs.

Conclusion

The 3D printing industry can seem extremely complicated, especially for beginners being confronted with a broad range of terminology. It requires a mix of practice, experience and knowledge to get 3D printing to work correctly. Additive manufacturing continues to evolve at a rapid pace, with new materials, smarter software and more capable machines expanding what’s possible every year. Whether you’re just getting started or looking to scale up your use of 3D printing, understanding the language behind the technology is the first step toward making confident, informed decisions.

If you have any questions or would like advice on materials or processes, reach out to us at print@3dpeople.uk and we will gladly answer any questions you might have.