A simulation of a product created prior to development for the purpose of testing or gathering feedback.

A prototype is a primitive representation or version of a product that a design team or front-end-development team typically creates during the design process.

The goal of a prototype is to test the flow of a design solution and gather feedback on it—from both internal and external parties—before constructing the final product. The state of a prototype is fluid as the team revises the design iteratively based on user feedback.