Which feature distinguishes FDM from other 3D printing technologies?

Fused Deposition Modelling (FDM) is distinct from other 3D printing technologies primarily because it utilizes thermoplastic filaments. In this process, a thermoplastic material is heated until it melts and then extruded layer by layer to build up the object. This feature is fundamental to FDM as it involves the manipulation of materials that can be easily molded and cooled, thus allowing for solidification into durable parts upon cooling.

This is in contrast to technologies such as resin-based printing, which employs photopolymer resins that are cured by ultraviolet light. While speed can be a factor in different methods, FDM is not specifically recognized as the fastest, and many other technologies can produce parts at comparable or even faster rates depending on the context. Furthermore, FDM does inherently build objects layer by layer, as is characteristic of most 3D printing techniques, so the idea of generating objects without layers is not an accurate representation of the FDM process.