On a basic level, printers can be broken down into two groups: FDM and resin. While each of these can have variable technology behind them, they effectively operate in the same way. FDM stands for ‘Fused deposition modeling’ and uses a motor to squeeze melted filament onto a moving bed, building your print layer-by-layer.
Filaments are available in a range of different materials, from standard ABS or PLA (polylactic acid) plastic, up to more niche materials such as wood pulp for sustainability, foam for flexibility and weight, and even sturdy carbon fibre if you wanted to try your hand at building a battle bot. This type of printer should be on your radar if you want to create props, cosplays, or larger models as it’s better equipped at handling large prints, though you may see some layer lines on the finished models.
Resin-based printers on the other hand, have a build plate that lowers into a vat of UV reactive liquid resin, with a screen underneath the tank that flashes UV light to build the model, again, layer-by layer. There are several styles of resin curing technology used, such as SLA (Stereolithography), MSLA (Masked Stereolithography) and DLP (Digital Light Process), though functionally they’ll all use UV light to cure your print in liquid resin, and that comes with its own set of problems.
Resin is a toxic substance and should be handled with care, so you’ll need protective equipment such as gloves, a respirator and a well-ventilated room in which to set up, and the size of your models is restricted by the tank size, but the trade-off is that models printed with resin are much, much more detailed than anything you can get on an FDM machine. This is good for tabletop miniatures or small, highly detailed prototyping.