[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"site-config":3,"topic:html-vs-xhtml-key-differences":6,"blog-categories":86,"course-tree":111},{"data":4},{"google_site_verification":5,"ga4_measurement_id":5,"site_name":5,"default_og_image":5,"twitter_handle":5},null,{"data":7},{"id":8,"title":9,"slug":10,"content":11,"course":12,"subcategory":15,"author":18,"reading_time_minutes":24,"cornerstone":25,"schema_type":26,"faq_json":5,"video_url":5,"canonical_url":27,"meta_title":28,"meta_description":29,"og_image":5,"toc_json":30,"code_examples":55,"quiz":64,"exercises":69,"published_at":5,"updated_at":77,"prev":78,"next":82},36,"HTML vs XHTML: Key Differences","html-vs-xhtml-key-differences","\u003Ch2 id=\"html-vs-xhtml-key-differences\">HTML vs XHTML: Key Differences\u003C\u002Fh2>\u003Cp>\u003Cstrong>Focus keyword: HTML vs XHTML\u003C\u002Fstrong> — a common interview and exam question that clarifies why modern web development standardized on HTML5 rather than the stricter XHTML.\u003C\u002Fp>\u003Ch3 id=\"1-what-is-xhtml\">1. What Is XHTML?\u003C\u002Fh3>\u003Cp>\u003Cstrong>XHTML (Extensible HyperText Markup Language)\u003C\u002Fstrong> is a stricter, XML-based reformulation of HTML. It requires documents to follow strict XML syntax rules, whereas regular HTML is more forgiving of minor errors.\u003C\u002Fp>\u003Ch3 id=\"2-key-syntax-differences\">2. Key Syntax Differences\u003C\u002Fh3>\u003Ctable>\u003Ctr>\u003Cth>Rule\u003C\u002Fth>\u003Cth>HTML\u003C\u002Fth>\u003Cth>XHTML\u003C\u002Fth>\u003C\u002Ftr>\u003Ctr>\u003Ctd>Tag closing\u003C\u002Ftd>\u003Ctd>Some tags can be left unclosed (e.g. <li>)\u003C\u002Ftd>\u003Ctd>All tags MUST be closed, including self-closing tags (<br \u002F>)\u003C\u002Ftd>\u003C\u002Ftr>\u003Ctr>\u003Ctd>Case sensitivity\u003C\u002Ftd>\u003Ctd>Tags\u002Fattributes are case-insensitive\u003C\u002Ftd>\u003Ctd>Tags\u002Fattributes MUST be lowercase\u003C\u002Ftd>\u003C\u002Ftr>\u003Ctr>\u003Ctd>Attribute quoting\u003C\u002Ftd>\u003Ctd>Quotes often optional\u003C\u002Ftd>\u003Ctd>All attribute values MUST be quoted\u003C\u002Ftd>\u003C\u002Ftr>\u003Ctr>\u003Ctd>Nesting\u003C\u002Ftd>\u003Ctd>Browsers often forgive improper nesting\u003C\u002Ftd>\u003Ctd>Must be strictly, properly nested\u003C\u002Ftd>\u003C\u002Ftr>\u003Ctr>\u003Ctd>Error handling\u003C\u002Ftd>\u003Ctd>Browser tries to recover and render anyway\u003C\u002Ftd>\u003Ctd>A single syntax error can stop the page from rendering (XML parsing error)\u003C\u002Ftd>\u003C\u002Ftr>\u003C\u002Ftable>\u003Ch3 id=\"3-why-html5-won\">3. Why HTML5 'Won'\u003C\u002Fh3>\u003Cp>HTML5, released after XHTML's peak, combined semantic improvements with HTML's flexible, error-tolerant parsing — making it far more practical for real-world development. Today, the vast majority of websites use standard HTML5 rather than XHTML.\u003C\u002Fp>\u003Ch3 id=\"4-is-xhtml-still-used\">4. Is XHTML Still Used?\u003C\u002Fh3>\u003Cp>XHTML still appears in some legacy enterprise systems, certain XML-based publishing pipelines (like ePub), and contexts requiring strict XML validation, but it's largely considered a legacy\u002Fniche technology in mainstream, trending front-end development.\u003C\u002Fp>\u003Ch3 id=\"5-practical-takeaway\">5. Practical Takeaway\u003C\u002Fh3>\u003Cp>Modern developers should write HTML5, but understanding XHTML's strict syntax rules (closing all tags, lowercase, quoted attributes) is still good practice for writing clean, well-formed markup regardless of which standard you use.\u003C\u002Fp>\u003Cdiv class=\"try-it-yourself language-html\">\u003Cpre>\u003Ccode><!-- Valid in HTML5, but technically 'loose' -->\n<ul>\n  <li>Item One\n  <li>Item Two\n<\u002Ful>\n<br>\n<img src=\"photo.jpg\">\u003C\u002Fcode>\u003C\u002Fpre>\u003C\u002Fdiv>\u003Cdiv class=\"try-it-yourself language-html\">\u003Cpre>\u003Ccode><!-- XHTML-strict equivalent: every tag closed, self-closing tags use \u002F> -->\n<ul>\n  <li>Item One<\u002Fli>\n  <li>Item Two<\u002Fli>\n<\u002Ful>\n<br \u002F>\n<img src=\"photo.jpg\" alt=\"Description\" \u002F>\u003C\u002Fcode>\u003C\u002Fpre>\u003C\u002Fdiv>",{"name":13,"slug":14},"HTML","html-tutorial",{"name":16,"slug":17},"Structuring Content","structuring-content",{"slug":19,"display_name":20,"job_title":5,"short_bio":5,"expertise_tags":21,"headshot":5,"long_bio":5,"credentials":5,"twitter_url":5,"linkedin_url":5,"github_url":5,"personal_website_url":5,"other_sameas_urls":5,"topics":22,"posts":23},"badar-khalil","Badar Khalil",[],[],[],1,false,"Article","https:\u002F\u002Fwpfsharp.com\u002Ftopics\u002Fhtml-vs-xhtml-key-differences","HTML vs XHTML: Syntax Rules & Key Differences Explained","Compare HTML and XHTML — syntax strictness, tag closing rules, case sensitivity, and why modern HTML5 replaced XHTML for most websites.",[31],{"id":10,"text":9,"level":32,"children":33},2,[34,39,43,47,51],{"id":35,"text":36,"level":37,"children":38},"1-what-is-xhtml","1. What Is XHTML?",3,[],{"id":40,"text":41,"level":37,"children":42},"2-key-syntax-differences","2. Key Syntax Differences",[],{"id":44,"text":45,"level":37,"children":46},"3-why-html5-won","3. Why HTML5 'Won'",[],{"id":48,"text":49,"level":37,"children":50},"4-is-xhtml-still-used","4. Is XHTML Still Used?",[],{"id":52,"text":53,"level":37,"children":54},"5-practical-takeaway","5. Practical Takeaway",[],[56,61],{"id":57,"language":58,"code":59,"is_editable":60},80,"html","\u003C!-- Valid in HTML5, but technically 'loose' -->\n\u003Cul>\n  \u003Cli>Item One\n  \u003Cli>Item Two\n\u003C\u002Ful>\n\u003Cbr>\n\u003Cimg src=\"photo.jpg\">",true,{"id":62,"language":58,"code":63,"is_editable":60},81,"\u003C!-- XHTML-strict equivalent: every tag closed, self-closing tags use \u002F> -->\n\u003Cul>\n  \u003Cli>Item One\u003C\u002Fli>\n  \u003Cli>Item Two\u003C\u002Fli>\n\u003C\u002Ful>\n\u003Cbr \u002F>\n\u003Cimg src=\"photo.jpg\" alt=\"Description\" \u002F>",{"id":65,"slug":66,"title":67,"time_limit_seconds":5,"pass_percentage":68,"question_count":24},20,"html-vs-xhtml-quiz","HTML vs XHTML Quiz",70,[70],{"id":71,"title":72,"slug":73,"prompt":74,"starter_code":75,"expected_output":76,"language":58,"order_index":24},34,"Convert Loose HTML to XHTML-Strict Style","convert-loose-html-to-xhtml-strict","Rewrite the markup below to follow strict XHTML-style rules: close every tag, self-close void elements with a trailing slash, use lowercase tags, and quote all attribute values.","\u003CDIV class=box>\n\u003CP>Some text\n\u003CIMG src=pic.jpg>\n\u003Cinput type=text>\n\u003C\u002FDIV>","All tags lowercase and properly closed, void elements self-closed (e.g. \u003Cimg ... \u002F>), and all attribute values in double quotes.","2026-09-27T17:47:24+00:00",{"id":79,"slug":80,"title":81},35,"html-url-encoding-explained","HTML URL Encoding Explained",{"id":83,"slug":84,"title":85},49,"html-forms-introduction","HTML Forms Introduction",{"data":87},[88,93,96,101,106],{"name":89,"slug":90,"description":91,"post_count":32,"subcategories":92},"CSS","css","Learn CSS with practical tutorials and examples covering layouts, Flexbox, Grid, responsive design, typography, positioning, animations, and more.",[],{"name":13,"slug":58,"description":94,"post_count":32,"subcategories":95},"Learn HTML with practical tutorials and examples for beginners. Explore HTML tags, elements, attributes, links, images, forms, semantic HTML, and more with clear explanations and real code examples.",[],{"name":97,"slug":98,"description":99,"post_count":24,"subcategories":100},"WPF","wpf","Learn WPF with practical tutorials and examples covering XAML, windows, controls, layouts, data binding, MVVM, commands, styles, templates, debugging, and modern WPF UI development.",[],{"name":102,"slug":103,"description":104,"post_count":24,"subcategories":105},"Python","python","Learn Python with practical tutorials covering strings, lists, functions, exceptions, files, packages, virtual environments, modules, classes, and beginner programming concepts.",[],{"name":107,"slug":108,"description":109,"post_count":24,"subcategories":110},"Java","java","Learn Java with practical tutorials and examples for beginners. Explore Java syntax, variables, data types, classes, objects, methods, inheritance, exceptions, collections, and more with clear explanations and real code examples.",[],{"data":112},[113],{"id":24,"name":13,"slug":14,"icon":5,"icon_url":5,"short_description":114,"meta_title":115,"meta_description":116,"og_image":117,"locale":118,"subcategories":119},"Welcome to our HTML Tutorial for Beginners, a complete guide designed to help you learn HTML from the ground up.\n\nHTML, which stands for HyperText Markup Language, is the standard language used to structure content on the web. Whether you want to become a web developer, build your own website, or continue learning CSS and JavaScript, understanding HTML is an essential first step.\n\nThis HTML course takes you through the fundamentals step by step, using simple explanations and practical examples. ","HTML Tutorial for Beginners - Learn HTML Step by Step","Learn HTML from scratch with our beginner-friendly HTML tutorial. Understand HTML tags, elements, forms, tables, links, images, semantic HTML and more with practical examples.","https:\u002F\u002Fwpfsharp.com\u002Fstorage\u002Fcourses\u002Fog\u002F01M2GK0XN45C0B937NF9XFAD4S.webp","en",[120,145,181,205,271,302,316,344,368,384],{"id":24,"name":121,"slug":122,"order_index":24,"topics":123},"HTML Fundamentals & Setup","html-fundamentals-setup",[124,127,130,133,137,141],{"id":24,"title":125,"slug":126,"order_index":24,"cornerstone":25,"reading_time_minutes":24},"HTML Introduction & History","html-introduction-and-history",{"id":32,"title":128,"slug":129,"order_index":24,"cornerstone":25,"reading_time_minutes":32},"HTML Editors & Environment Setup","html-editors-and-environment-setup",{"id":37,"title":131,"slug":132,"order_index":37,"cornerstone":25,"reading_time_minutes":32},"HTML Basic Syntax & Document Structure","html-basic-syntax-document-structure",{"id":134,"title":135,"slug":136,"order_index":134,"cornerstone":25,"reading_time_minutes":32},4,"HTML Elements & Tags Explained","html-elements-tags-explained",{"id":138,"title":139,"slug":140,"order_index":138,"cornerstone":25,"reading_time_minutes":32},5,"HTML Attributes (Global & Standard)","html-attributes-global-standard",{"id":142,"title":143,"slug":144,"order_index":142,"cornerstone":25,"reading_time_minutes":32},6,"Understanding the DOCTYPE & HTML5 Boilerplate","understanding-doctype-html5-boilerplate",{"id":32,"name":146,"slug":147,"order_index":32,"topics":148},"Text & Content Basics","text-content-basics",[149,153,157,161,165,169,173,177],{"id":150,"title":151,"slug":152,"order_index":150,"cornerstone":25,"reading_time_minutes":32},7,"HTML Headings (H1–H6) & SEO Best Practices","html-headings-h1-h6-seo-best-practices",{"id":154,"title":155,"slug":156,"order_index":154,"cornerstone":25,"reading_time_minutes":32},8,"HTML Paragraphs & Line Breaks","html-paragraphs-line-breaks",{"id":158,"title":159,"slug":160,"order_index":158,"cornerstone":25,"reading_time_minutes":24},9,"HTML Text Formatting (Bold, Italic, Mark, etc.)","html-text-formatting-bold-italic-mark",{"id":162,"title":163,"slug":164,"order_index":162,"cornerstone":25,"reading_time_minutes":32},10,"HTML Styles (Inline CSS Basics)","html-styles-inline-css-basics",{"id":166,"title":167,"slug":168,"order_index":166,"cornerstone":25,"reading_time_minutes":32},11,"HTML Quotations & Citations (blockquote, q, cite)","html-quotations-citations-blockquote-q-cite",{"id":170,"title":171,"slug":172,"order_index":170,"cornerstone":25,"reading_time_minutes":32},12,"HTML Comments (Best Practices)","html-comments-best-practices",{"id":174,"title":175,"slug":176,"order_index":174,"cornerstone":25,"reading_time_minutes":32},13,"HTML Colors (Names, HEX, RGB, HSL)","html-colors-names-hex-rgb-hsl",{"id":178,"title":179,"slug":180,"order_index":178,"cornerstone":25,"reading_time_minutes":32},14,"HTML & CSS Integration (Inline, Internal, External)","html-css-integration-inline-internal-external",{"id":37,"name":182,"slug":183,"order_index":37,"topics":184},"Links, Media & Navigation","links-media-navigation",[185,189,193,197,201],{"id":186,"title":187,"slug":188,"order_index":186,"cornerstone":25,"reading_time_minutes":32},15,"HTML Links (Anchor Tags & Hyperlinks)","html-links-anchor-tags-hyperlinks",{"id":190,"title":191,"slug":192,"order_index":190,"cornerstone":25,"reading_time_minutes":32},16,"HTML Images (Alt Text, Lazy Loading, Formats)","html-images-alt-text-lazy-loading-formats",{"id":194,"title":195,"slug":196,"order_index":194,"cornerstone":25,"reading_time_minutes":24},17,"HTML Favicon Setup","html-favicon-setup",{"id":198,"title":199,"slug":200,"order_index":198,"cornerstone":25,"reading_time_minutes":32},18,"HTML Page Title & Meta Tags (SEO Essentials)","html-page-title-meta-tags-seo-essentials",{"id":202,"title":203,"slug":204,"order_index":202,"cornerstone":25,"reading_time_minutes":32},19,"HTML File Paths (Absolute vs Relative)","html-file-paths-absolute-vs-relative",{"id":134,"name":16,"slug":17,"order_index":134,"topics":206},[207,211,216,221,226,230,234,238,242,246,250,254,258,262,266,269,270],{"id":208,"title":209,"slug":210,"order_index":65,"cornerstone":25,"reading_time_minutes":32},24,"HTML Tables Explained: Rows, Columns & Merging Cells","html-tables-rows-columns-merging-cells",{"id":212,"title":213,"slug":214,"order_index":215,"cornerstone":25,"reading_time_minutes":32},25,"HTML Lists: Ordered, Unordered & Description Lists","html-lists-ordered-unordered-description",21,{"id":217,"title":218,"slug":219,"order_index":220,"cornerstone":25,"reading_time_minutes":32},26,"HTML Block vs Inline Elements Explained","html-block-vs-inline-elements",22,{"id":222,"title":223,"slug":224,"order_index":225,"cornerstone":25,"reading_time_minutes":24},27,"HTML Div & Span: Generic Containers Explained","html-div-and-span-containers",23,{"id":227,"title":228,"slug":229,"order_index":208,"cornerstone":25,"reading_time_minutes":32},28,"HTML Classes vs ID: Selectors Explained","html-classes-vs-id-selectors-explained",{"id":231,"title":232,"slug":233,"order_index":212,"cornerstone":25,"reading_time_minutes":24},29,"HTML Iframes: Embedding External Content","html-iframes-embedding-content",{"id":235,"title":236,"slug":237,"order_index":217,"cornerstone":25,"reading_time_minutes":32},30,"HTML Head Element Deep Dive","html-head-element-deep-dive",{"id":239,"title":240,"slug":241,"order_index":222,"cornerstone":25,"reading_time_minutes":32},31,"HTML Layout Techniques: Header, Nav & Footer","html-layout-techniques-header-nav-footer",{"id":243,"title":244,"slug":245,"order_index":227,"cornerstone":25,"reading_time_minutes":32},32,"Responsive HTML Design: Mobile-First Approach","responsive-html-design-mobile-first-approach",{"id":247,"title":248,"slug":249,"order_index":231,"cornerstone":25,"reading_time_minutes":37},74,"HTML Semantic Elements (article, section, aside, nav)","html-semantic-elements-article-section-aside-nav",{"id":251,"title":252,"slug":253,"order_index":235,"cornerstone":25,"reading_time_minutes":32},75,"HTML Style Guide & Coding Conventions","html-style-guide-coding-conventions",{"id":255,"title":256,"slug":257,"order_index":239,"cornerstone":25,"reading_time_minutes":32},76,"HTML Entities & Special Characters","html-entities-special-characters",{"id":259,"title":260,"slug":261,"order_index":243,"cornerstone":25,"reading_time_minutes":24},77,"HTML Symbols","html-symbols",{"id":263,"title":264,"slug":265,"order_index":263,"cornerstone":25,"reading_time_minutes":24},33,"HTML Emojis 😀: How to Use Them in Web Pages","html-emojis-trending-guide",{"id":71,"title":267,"slug":268,"order_index":71,"cornerstone":25,"reading_time_minutes":32},"HTML Character Sets: UTF-8 & Encoding Explained","html-character-sets-utf-8-encoding",{"id":79,"title":81,"slug":80,"order_index":79,"cornerstone":25,"reading_time_minutes":24},{"id":8,"title":9,"slug":10,"order_index":8,"cornerstone":25,"reading_time_minutes":24},{"id":150,"name":272,"slug":273,"order_index":138,"topics":274},"Forms & User Input","forms-user-input",[275,277,282,287,292,297],{"id":83,"title":85,"slug":84,"order_index":276,"cornerstone":25,"reading_time_minutes":32},37,{"id":278,"title":279,"slug":280,"order_index":281,"cornerstone":25,"reading_time_minutes":24},50,"HTML Form Attributes (action, method, etc.)","html-form-attributes-action-method",38,{"id":283,"title":284,"slug":285,"order_index":286,"cornerstone":25,"reading_time_minutes":24},51,"HTML Form Elements (input, select, textarea, button)","html-form-elements-input-select-textarea-button",39,{"id":288,"title":289,"slug":290,"order_index":291,"cornerstone":25,"reading_time_minutes":32},52,"HTML Input Types (Modern Types: email, date, color, range)","html-input-types-modern-email-date-color-range",40,{"id":293,"title":294,"slug":295,"order_index":296,"cornerstone":25,"reading_time_minutes":32},53,"HTML Input Attributes (required, placeholder, pattern)","html-input-attributes-required-placeholder-pattern",41,{"id":298,"title":299,"slug":300,"order_index":301,"cornerstone":25,"reading_time_minutes":32},54,"HTML Form Validation (Client-Side)","html-form-validation-client-side",42,{"id":154,"name":303,"slug":304,"order_index":142,"topics":305},"Graphics & Visuals","graphics-visuals",[306,311],{"id":307,"title":308,"slug":309,"order_index":310,"cornerstone":25,"reading_time_minutes":37},55,"HTML Canvas (2D Drawing API) 🔥","html-canvas-2d-drawing-api",43,{"id":312,"title":313,"slug":314,"order_index":315,"cornerstone":25,"reading_time_minutes":37},56,"HTML SVG (Scalable Vector Graphics)","html-svg-scalable-vector-graphics",44,{"id":158,"name":317,"slug":318,"order_index":150,"topics":319},"Multimedia","multimedia",[320,325,330,335,340],{"id":321,"title":322,"slug":323,"order_index":324,"cornerstone":25,"reading_time_minutes":32},57,"HTML Media Overview","html-media-overview",45,{"id":326,"title":327,"slug":328,"order_index":329,"cornerstone":25,"reading_time_minutes":32},58,"HTML Video Embedding (Native Player)","html-video-embedding-native-player",46,{"id":331,"title":332,"slug":333,"order_index":334,"cornerstone":25,"reading_time_minutes":32},59,"HTML Audio Embedding","html-audio-embedding",47,{"id":336,"title":337,"slug":338,"order_index":339,"cornerstone":25,"reading_time_minutes":32},60,"HTML Plug-ins (Object & Embed Tags)","html-plugins-object-embed-tags",48,{"id":341,"title":342,"slug":343,"order_index":83,"cornerstone":25,"reading_time_minutes":32},61,"Embedding YouTube Videos in HTML","embedding-youtube-videos-in-html",{"id":162,"name":345,"slug":346,"order_index":154,"topics":347},"HTML5 Web APIs (Advanced\u002FTrending)","html5-web-apis-advancedtrending",[348,352,356,360,364],{"id":349,"title":350,"slug":351,"order_index":278,"cornerstone":25,"reading_time_minutes":32},62,"HTML Geolocation API","html-geolocation-api",{"id":353,"title":354,"slug":355,"order_index":283,"cornerstone":25,"reading_time_minutes":32},63,"HTML Drag & Drop API","html-drag-and-drop-api",{"id":357,"title":358,"slug":359,"order_index":288,"cornerstone":25,"reading_time_minutes":32},64,"HTML Web Storage (localStorage & sessionStorage)","html-web-storage-localstorage-sessionstorage",{"id":361,"title":362,"slug":363,"order_index":293,"cornerstone":25,"reading_time_minutes":32},65,"HTML Web Workers (Background Processing)","html-web-workers-background-processing",{"id":365,"title":366,"slug":367,"order_index":298,"cornerstone":25,"reading_time_minutes":32},66,"HTML Server-Sent Events (SSE)","html-server-sent-events-sse",{"id":166,"name":369,"slug":370,"order_index":158,"topics":371},"Accessibility & Best Practices (High-Demand  Skill) �","accessibility-best-practices-high-demand-skill",[372,376,380],{"id":373,"title":374,"slug":375,"order_index":307,"cornerstone":25,"reading_time_minutes":32},67,"HTML Accessibility (ARIA, Screen Readers)","html-accessibility-aria-screen-readers",{"id":377,"title":378,"slug":379,"order_index":312,"cornerstone":25,"reading_time_minutes":32},68,"Writing Semantic & SEO-Friendly HTML","writing-semantic-and-seo-friendly-html",{"id":381,"title":382,"slug":383,"order_index":321,"cornerstone":25,"reading_time_minutes":32},69,"HTML Performance Optimization Basics","html-performance-optimization-basics",{"id":170,"name":385,"slug":386,"order_index":162,"topics":387},"Reference & Practice","reference-practice",[388,391,395,399,403,407,411,414],{"id":68,"title":389,"slug":390,"order_index":24,"cornerstone":25,"reading_time_minutes":32},"HTML Tag List (Full Reference)","html-tag-list-full-reference",{"id":392,"title":393,"slug":394,"order_index":32,"cornerstone":25,"reading_time_minutes":32},71,"HTML Global Attributes Reference","html-global-attributes-reference",{"id":396,"title":397,"slug":398,"order_index":37,"cornerstone":25,"reading_time_minutes":32},72,"HTML Events Reference","html-events-reference",{"id":400,"title":401,"slug":402,"order_index":134,"cornerstone":25,"reading_time_minutes":32},73,"HTML Browser Support & Compatibility","html-browser-support-compatibility",{"id":404,"title":405,"slug":406,"order_index":138,"cornerstone":25,"reading_time_minutes":32},78,"HTML Doctypes Reference","html-doctypes-reference",{"id":408,"title":409,"slug":410,"order_index":142,"cornerstone":25,"reading_time_minutes":32},79,"HTTP Methods & Messages (Basics for Forms\u002FAPIs)","http-methods-messages-basics",{"id":57,"title":412,"slug":413,"order_index":150,"cornerstone":25,"reading_time_minutes":37},"HTML Interview Preparation (Top Q&A)","html-interview-preparation-top-qa",{"id":62,"title":415,"slug":416,"order_index":154,"cornerstone":25,"reading_time_minutes":24},"HTML Quiz & Practice Exercises","html-quiz-practice-exercises"]