Real-world mechanisms, state management, edge cases, performance trade-offs, and practical coding.
<section>: Groups thematic content, usually with a heading. Represents a generic section of a document.<article>: Encapsulates self-contained, independent content that could be distributed/reused standalone (e.g., blog post, forum card).<nav>: Declares a block of major navigation links.<aside>: Identifies auxiliary or tangent content located away from the main text flow (sidebars, callouts).<header>: Wraps introductory content, navigational aid, or branding (logo, title, search).<footer>: Contains footer metadata, copyright details, contact information, or sitemap links.DOMContentLoaded: Fired when the HTML document is fully parsed and the DOM tree is built, without waiting for external assets like images, stylesheets, and iframes to finish loading.load: Fired only when the entire page, including all dependent resources (images, stylesheets, subframes), is fully loaded.dns-prefetch: Resolves domain IP addresses early in the background to reduce DNS latency.<link rel="dns-prefetch" href="//example.com">preconnect: Establishes early connection handshakes (DNS, TCP, TLS) with an external domain.<link rel="preconnect" href="https://example.com" crossorigin>preload: Forces browser to download high-priority assets (fonts, hero images) immediately during initial parsing.<link rel="preload" href="font.woff2" as="font" type="font/woff2" crossorigin>prefetch: Downloads low-priority assets during idle time, anticipating user navigation to other pages.<link rel="prefetch" href="next-page.html">You've completed the 5 free sample questions. Get unrestricted lifetime access to every question, model answer, implementation challenge, and all 27+ technologies for a single payment.
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