Product architecture refers to the organization and structure of a software product. It's like the blueprint that determines how all the different components of the product fit together to create a cohesive and functional whole. Just like a well-designed building, a good product architecture makes it easier for developers to build and maintain the product. It ensures that the product is scalable, robust, and easy to extend or modify in the future. In simpler terms, product architecture is the framework that holds everything together and determines how the product works behind the scenes.