A Single Page Application (SPA) is a web application that loads a single HTML page and dynamically updates content as the user interacts with the app. This approach allows for a smoother user experience, as it reduces the need for full page reloads, making the application feel more like a desktop application. SPAs often use frameworks like React, Angular, or Vue.js to manage the user interface and handle data. In SPAs, navigation between different sections of the app is typically managed through JavaScript, which updates the URL without reloading the page. This technique enhances performance and provides a more seamless experience. However, SPAs can face challenges with search engine optimization (SEO) and initial loading times, requiring specific strategies to address these issues.