A feature model is a structured representation used in software engineering to define and manage the features of a system or product. It helps in understanding the relationships between different features, such as which features are mandatory, optional, or alternative. This model is particularly useful in product line engineering, where multiple products share common features but also have unique characteristics. Feature models typically use a tree-like structure to illustrate these relationships, making it easier for stakeholders to visualize and analyze the options available. By employing a feature model, teams can streamline the development process, ensuring that all necessary features are considered and integrated effectively into the final product.