SPA (Single Page Application) is a web development approach with web applications that load an entire web page at once when a user navigates to the page. Instead of loading multiple pages, only one page is rendered. This helps improve performance, user experience, and allows for features like push state and real-time updates. For example, when a user clicks on a link, instead of a request being sent to the server, the current page's JavaScript code can make an API call and update the view accordingly. This prevents full page refreshes and makes the web application feel more like a native app. For more information check out the MDN Web Docs here.