Kitbashing is a technique in model railroading where parts from different kits are combined to create a unique and custom model. This can include using parts from multiple kits to build a single model, or using parts from kits to enhance or modify existing models. The term "kitbashing" comes from the idea of physically bashing or breaking apart kits to use the parts for this process.

Scratchbuilding is a technique in model railroading where a model is built from scratch using raw materials, rather than from a kit. This often involves creating each part of the model by hand, such as by cutting, shaping, and assembling pieces of wood, plastic, metal, or other materials to create a unique and custom model. Scratchbuilding is a highly skilled and time-consuming process, but it allows modelers to create one-of-a-kind models that are not available as commercial kits.