Model Robots is an area of modeling with its origin in the fictional Japanese anime genre of mecha. They are usually marketed in 1:100 and 1:144 scales, although 1:60 scale models exist. The majority of model robots are produced by Bandai and are based on the Mobile Suit Gundam anime metaseries. This has given rise to the hobby's common name in Japan, Gunpla (a portmanteau of "Gundam" and "plastic model").

Bandai models are generally color-injection plastic with snap-together construction. Thus, they do not require glue or paint, although the use of them will greatly enhance the model's appearance. Articulation is accomplished by the use of polycaps; Master Grade and high models use durable ABS plastic to allow many different poses without wearing out.

Gunpla is a major hobby in Japan, with entire magazines dedicated to variations on Bandai models. As mecha are fictional humanoid objects, there is considerable leeway for custom models and "kitbashes." A large amount of artistry goes in to action poses and personalized variations on classic machines. There is also a market for custom resin kits which fill in gaps in the Bandai model line.

Gundam is not the only line of model robots. Neon Genesis Evangelion, Patlabor, Dunbine and L-Gaim, to name a few, are all represented by Bandai model lines.

The tradition of Gunpla is so important that Daisuke Enomoto, a 34-year-old Japanese man who is slated to be the world's 4th space tourist, planned to dress up as Char Aznable and build his favorite Gunpla on the ISS.

                                             From: Wikipedia