1. Compare SSR, SSG, and ISR: when should you use each rendering strategy?
Use SSR with getServerSideProps when data must be fresh on every request or is user-specific like dashboards, personalized feeds, or real-time data, accepting slower initial loads for guaranteed current content. Use SSG with getStaticProps for content that rarely changes like marketing pages, documentation, or blog posts to achieve the fastest possible load times and lowest server costs by pre-rendering at build time. Use ISR when content updates periodically but not constantly like e-commerce products, news articles, or social media feeds, combining SSG's speed with the ability to update content without full rebuilds by setting a revalidate period. Consider that SSG with ISR offers the best of both worlds for most content sites, SSR is necessary for truly dynamic per-request data, and CSR works for interactive features that don't need SEO.