A prototype is an early sample, model, or release of a product built to test a concept or process. In the context of web design, a prototype serves as an interactive mockup of your proposed website design. Although it may not have all the features and functionality of a final website, it can give you a good idea of the user journey and flow through the site.
Creating a website prototype allows you to link between screens and demonstrate how the website would work before committing to a full build. This can be an invaluable tool in the early stages of web design, helping to avoid potential problems and save time and resources further down the line.