React follows a major-version-centric documentation strategy to help developers stay aligned with stable API behavior while allowing flexibility across legacy and modern versions.

1. Overview
2. Versioning Policy
3. Archived Documentation
4. Legacy Site Structure
5. React 19 Timeline and Expert Summary
   • React 19 Overview
   • React v19.0.0 (December 2024)
   • React v19.1.0 (March 2025)
   • React 19 Expert Summary
6. React 18 Timeline and Expert Summary
   • React 18 Overview
   • React v18.0.0 (March 2022)
   • React v18.1.0 (April 2022)
   • React v18.2.0 (June 2022)
   • React v18.3.0 (April 2024)
   • React v18.3.1 (April 2024)
   • React 18 Expert Summary
7. React 17 Timeline and Expert Summary
   • React 17 Overview
   • React v17.0.0 (October 2020)
   • React v17.0.1 (October 2020)
   • React v17.0.2 (March 2021)
   • React 17 Expert Summary
8. React 16 Timeline and Expert Summary
   • React 16 Overview
   • React v16.0 (September 2017)
   • React v16.1 - v16.2.x
   • React v16.3.x (March - August 2018)
   • React v16.4 - v16.5.x (May - September 2018)
   • React v16.6.x (October - November 2018)
   • React v16.7.0 (December 2018)
   • React v16.8.x (February - March 2019)
   • React v16.9 - v16.10.x (August - October 2019)
   • React v16.11 - v16.14.0 (2019 - 2020)
   • React 16 Expert Summary
9. React 15 Timeline and Expert Summary
   • React 15 Overview
   • React v15.0.0 (April 2016)
   • React v15.0.1 - v15.0.2
   • React v15.1.0 (May 2016)
   • React v15.2.0 - v15.2.1
   • React v15.3.0 - v15.3.2
   • React v15.4.0 - v15.4.2
   • React v15.5.0 - v15.5.4
   • React v15.6.0 - v15.6.2
   • React v15.7.0 (October 2017)
   • React 15 Expert Summary
10. React 0.14 Timeline and Expert Summary
    • React 0.14 Overview
    • React v0.14.0 (October 2015)
    • React v0.14.1 (October 2015)
    • React v0.14.2 (November 2015)
    • React v0.14.3 (November 2015)
    • React v0.14.4 (December 2015)
    • React v0.14.5 (December 2015)
    • React v0.14.6 (January 2016)
    • React v0.14.7 (January 2016)
    • React v0.14.8 (March 2016)
    • React v0.14.10 (October 2020)
    • React 0.14 Expert Summary
11. React 0.13 Timeline and Expert Summary
    • React 0.13 Overview
    • React v0.13.0 (March 2015)
    • React v0.13.1 (March 2015)
    • React v0.13.2 (April 2015)
    • React v0.13.3 (May 2015)
    • Expert 0.13 Summary
12. React 0.12 Timeline and Expert Summary
    • React 0.12 Overview
    • React v0.12.0 (October 2014)
    • React v0.12.1 (November 2014)
    • React v0.12.2 (December 2014)
    • React 0.12 Expert Summary
13. React 0.11 Timeline and Expert Summary
    • React 0.11 Overview
    • React v0.11.0 (July 2014)
    • React v0.11.1 (July 2014)
    • React v0.11.2 (September 2014)
    • React 0.11 Expert Summary
14. React Versions 0.x Timeline (v0.3.0 to v0.10.0)
    • Key Characteristics of the Era
    • HTML/SVG Alignment & DOM Compatibility (v0.8.0 – v0.10.0)
    • Expert Perspective
    • Key Takeaways
    • React v0.10.0 (March 2014)
    • React v0.9.0 (February 2014)
    • React v0.8.0 (December 2013)
    • React v0.5.0 - v0.5.2 (October–December 2013)
    • React v0.4.0 - v0.4.1 (July 2013)
    • React v0.3.1 - v0.3.3 (May–June 2013)
    • React v0.3.0 (May 2013)
15. Expert Summary

• The official documentation for the latest React version is hosted at react.dev.
• Minor and patch versions are not separately documented.
• Documentation is updated within each major version.
• Archived docs are accessible via x.react.dev where x is the major version.

React publishes updated documentation only for major releases:

• Patch and minor version changes are included within the major version’s site.
• When a new major release occurs:
  • The previous version’s documentation is frozen and moved to a subdomain.
  • Example: React 18 docs are archived at 18.react.dev.

For versions older than React 15, use:

• 15.react.dev

• React 18 was the first version with the new documentation site (react.dev).
• Older versions (React 17 and below) use legacy.reactjs.org.
• The new site focuses on:
  • Modern features like hooks
  • Updated examples
  • Improved navigation and explanations

React 19 represents the compiler era of React. It introduces the React Compiler (Beta), deeper integration of auto-memoization, HTML coordination, and marks a new phase of performance and DX improvements that reshape how React apps are authored and optimized.

React 19 introduces a source-to-source compiler that automatically optimizes components. This shift improves render performance and reduces manual memo or useCallback usage. React also expands SSR capabilities and HTML streaming coordination to modernize server-rendered workflows.

• React Compiler (Beta):
  • Auto-memoizes components at compile time.
  • Reduces re-renders without manual hooks.
• HTML Coordination APIs:
  • More declarative control over markup streaming.
• use() hook introduced for streaming async values in Suspense.

• Reduces manual optimization effort.
• Lays groundwork for full concurrent composability.
• Improves Suspense integration with streaming SSR.

• Compiler is opt-in and requires Babel or TypeScript integration.
• Some advanced patterns (refs, closures) may behave differently under the compiler.

• React 19 is about declarative optimization at scale, bridging gaps between runtime and compile-time behavior.

• Stability updates to the React Compiler.
• Expanded Suspense boundary support for SSR fallbacks.
• Better diagnostics and dev mode warnings.

React 19 shifts React from a manual optimization model to a compiler-assisted architecture—changing how performance is achieved in apps.

• Compiler-first Design: Transforms the way React handles reactivity and state change propagation.
• Suspense Evolution: With the use() hook, asynchronous rendering is more seamless and scalable.
• SSR Streaming: HTML coordination improves progressive rendering of server-side React apps.
• Developer Productivity: Less need for useMemo, useCallback, or manual React.memo.

React 19 is a strategic leap toward a more intuitive, performance-automated future, aligning React with modern expectations for DX and scalability.

React 18 is a landmark release introducing Concurrent Rendering, automatic batching, startTransition, and major improvements to Suspense and SSR hydration. It’s a performance-focused version that modernizes React’s runtime while maintaining backward compatibility.

React 18 introduced the Concurrent Renderer—a new rendering engine that enables React to pause, interrupt, and resume work. This allows for smoother UX under heavy computation and dramatically improves scalability for large apps.

• Concurrent rendering (opt-in).
• Automatic batching for setState in async contexts.
• startTransition() for low-priority UI updates.
• useId() hook for consistent SSR hydration.
• Improved support for React.lazy() and Suspense.

• Backward-compatible with React 17 apps.
• Required createRoot() instead of ReactDOM.render() for concurrent features.

• Minor bug fixes and early SSR streaming support improvements.

• Improved hydration resilience.
• Stabilization of useId and startTransition.
• Updates to automatic batching under complex effects.

• Internal preparations for React 19’s Compiler.
• Better development-mode warnings and debug messages.
• Enhanced Suspense support in edge cases.

• Patch for SSR crash scenarios.
• Miscellaneous fixes related to streaming hydration.
• Developer toolchain improvements.

React 18 is the performance era of React. It’s engineered for modern apps where rendering should be non-blocking, streaming, and flexible.

• Concurrent Mode: Unlocks features like Suspense, startTransition, and responsive UI rendering.
• Automatic Batching: Reduces unnecessary renders across async boundaries.
• SSR Hydration: Faster, more reliable server-side rendering.
• Transitional APIs: Maintains full backward compatibility with class and function components.

React 18 makes React smoother, smarter, and more scalable—critical for modern apps, SPAs, and streaming platforms.

React 17 was a foundational release with a strong emphasis on gradual upgrades, backward compatibility, and modernized event delegation. While it introduced no new features for the developer API, it laid the infrastructure groundwork for React 18 and beyond.

React 17 focused on preparing the ecosystem for the future. It was the first version that allowed incremental adoption of future React versions without needing to rewrite entire applications. This was made possible through changes in event delegation, internal refactors, and cleanup of legacy browser behaviors.

• No new developer-facing APIs.
• Modernized event system:
  • Events attached to the root DOM container rather than document.
• Improved support for concurrent rendering preparation.
• Upgraded error boundaries behavior.

• Enables embedding multiple React versions on a single page.
• Compatible with legacy and modern environments simultaneously.
• No need to upgrade all components to use React 17 APIs.

• No features like Suspense improvements or new hooks (those came in React 18).
• Still relies on class components for error boundaries.

• A highly strategic release, React 17 focused on flexibility and stability across large and legacy codebases.

• Bug fixes for hydration and event propagation.
• Minor compatibility enhancements for React DOM in edge cases.

• Further fixes to edge-case hydration mismatches.
• Stability improvements for embedding React within non-React apps.
• Bug fixes for synthetic events and legacy support.

React 17 is often called the “stepping stone release”. Though it lacked new developer APIs, its backward-compatible architecture and incremental upgrade strategy made it crucial for teams managing large production apps.

• Event Delegation Overhaul: By moving delegation from document to the root container, React became more sandbox-friendly.
• Incremental Upgrades: Made it possible to migrate React apps version-by-version—paving the way for React 18's concurrent features.
• Improved Compatibility: Allowed embedding or running multiple versions of React on a single page—useful for micro-frontends and hybrid platforms.
• Zero Feature, Maximum Strategy: It’s a powerful example of release planning focused on infrastructure maturity and ecosystem readiness.

React 17 is essential knowledge for any React expert, especially those working in large-scale, enterprise-grade apps requiring long-term maintainability.

React 16 was a massive architectural shift introducing the new Fiber architecture, Error Boundaries, Fragments, and the groundbreaking Hooks API. It transformed how developers manage component state, side effects, and render performance.

React 16 was a complete rewrite of React’s core with the introduction of Fiber, a new rendering engine. It enabled interruptible rendering, better error handling, and laid the foundation for hooks, suspense, and concurrent rendering.

• Fiber architecture: asynchronous rendering.
• Error boundaries via componentDidCatch.
• Return arrays and strings from render() (Fragments).
• Portals for rendering outside the DOM hierarchy.

• Massive step forward in performance and stability.
• Fixes for long-standing pain points in rendering logic.

• React.Fragment short syntax (<>) added.
• Improved SSR hydration.
• Miscellaneous bug fixes for the new Fiber internals.

• New Context API (stable).
• getDerivedStateFromProps lifecycle method.
• createRef() API for ref management.
• Introduced forwardRef() and React.memo() (for optimization).

• Pointer events support added.
• react-devtools hooks updated.
• Introduced support for lazy() and Suspense (code splitting).

• Introduced React.lazy() and Suspense officially.
• contextType static property added.
• Performance improvements to memoized components.

• Note: No hooks yet, but experimental preparation for hooks.

• useState, useEffect, useContext, useRef, useMemo, useReducer, useCallback
• Enabled functional components to use state and lifecycle logic.

• Introduced act() testing utility.
• Deprecated legacy string refs.
• Bug fixes in concurrent mode devtools and scheduler.

• Minor improvements to hook behavior.
• useDeferredValue, useTransition (experimental).
• Improved SSR, React.lazy() stabilization.
• v16.14.0: compatibility release for React 17 transition.

React 16 is one of the most important milestones in React’s evolution. It brought modern rendering paradigms, cutting-edge component ergonomics, and better performance and tooling for large-scale applications.

• Fiber Engine: Enabled concurrent rendering, suspense, and priority-based updates.
• Hooks: Removed the need for class components in most use cases.
• Error Boundaries: Added production-ready crash resilience.
• Context API + Memoization: Better state control and performance in large trees.
• Modular APIs: React.lazy(), Suspense, forwardRef() provided clean, optimized composability.

React 16 was more than a version bump—it was a complete rethinking of React's design philosophy.

React 15 was a crucial step in React’s transition from its early architecture to modern capabilities. It emphasized render fidelity, error boundaries, and laid important foundations for the upcoming Fiber architecture in React 16.

React 15 introduced more accurate rendering, HTML attribute normalization, and deprecation warnings for legacy patterns. It also marked the end of support for IE8, allowing cleaner DOM abstraction.

• Split rendering engine into ReactDOM and React Native.
• No more IE8 support.
• Better normalization of SVG and form element attributes.
• dangerouslySetInnerHTML safety enhancements.

• Rendering accuracy became a priority.
• Supported cleaner HTML spec-aligned output.

• Bug fixes and consistency patches around text input fields and attribute merging.

• Added support for custom elements.
• Allowed unknown attributes on DOM nodes.

• Introduced PropTypes warnings for invalid props.
• Better handling of whitespace in JSX rendering.

• Introduced react-test-renderer.
• Early preparation for Fiber through internal refactor.
• Improved warnings and memory leak detection.

• Separated React and ReactDOM packages for independent upgrades.
• Support for <details> and <summary> HTML tags.

• Moved PropTypes and CreateClass to external packages (prop-types, create-react-class).
• Start of legacy API deprecation.
• Better dev-only warnings.

• Improved onChange for checkbox/radio inputs.
• Enabled new keyboard event normalization.
• Bug fixes in text selection and controlled inputs.

• Final minor update in 15.x series.
• Contained forward-compatibility fixes for React 16 migration.
• Minor bug cleanup in synthetic event system.

React 15 signaled the last iteration of the classic rendering engine before Fiber. It emphasized spec-aligned DOM behavior, long-term maintainability, and developer experience.

• Deprecation Enforcement: React 15 began preparing the community for breaking changes by isolating legacy APIs.
• DOM Compatibility: HTML5 standards were prioritized.
• Tooling Enhancements: The react-test-renderer became a vital part of the React testing ecosystem.
• Performance Awareness: Paved the way for asynchronous rendering via early internal refactors.

React 15 was a steady, thoughtful evolution of React's internals and developer ergonomics, setting the stage for the groundbreaking React 16.

React 0.14 was a defining release in React's journey toward modularity and scalability. It introduced the separation of React and ReactDOM, support for stateless functional components, and significant refinements to component lifecycle management.

React 0.14 emphasized architectural modularity and refinement. Its most important change was splitting React into two packages: react and react-dom, paving the way for native rendering engines like React Native.

• Split React core into react and react-dom.
• First-class support for stateless functional components.
• New ReactDOM.findDOMNode abstraction.
• Composite components can now return arrays of elements.

• Separation of concerns allowed React to scale to multiple renderers.
• Functional components became first-class citizens.

• No built-in memoization or context APIs for functional components.

• Prepared React for extensibility (DOM, Native, VR, etc.) by decoupling rendering logic.

• Bug fixes for setState behavior and warning messages.

• Minor polish for 0.14.0 rollout.

• Bug fixes around dangerouslySetInnerHTML and invalid prop types.

• Focused on developer safety and spec adherence.

• Warnings added for invalid JSX nesting.
• Better error boundary fallback support.

• Fixed class-related inheritance bugs in React.createClass.

• Internal reconciler optimization.
• Better handling of controlled components.

• Compatibility improvements with React Native.
• Minor SSR bug fixes.

• Patches for event bubbling and focus delegation.

• Stability updates and IE9 fixes.

• Critical security patches applied retroactively.
• No new features; long-term maintenance.

React 0.14 formalized architectural separation and adopted a more scalable mindset. By enabling stateless components and separating DOM rendering, React set the foundation for:

• Cross-platform Rendering: Enabled React Native and custom renderers via react-dom, react-native, etc.
• Stateless Components: Encouraged pure functions over classes when lifecycle/state is not needed.
• Community Modularity: Allowed core updates without affecting rendering layers.

React 0.14 wasn't just about new features — it restructured React to support the ecosystem's explosive growth. With better error messaging, strict mode preparation, and rendering decoupling, React became a flexible and robust platform, not just a library.

React 0.13 marked a major evolution in how developers wrote components. It introduced ES6 class support, laid the groundwork for functional stateless components, and refined component lifecycles and rendering mechanics.

React 0.13 introduced ES6 classes, stateless functional components, and the new JSX transform. It was a pivotal step toward modern JavaScript compatibility and better code organization.

• Support for ES6 class components using extends React.Component.
• Introduced functional stateless components (no lifecycle, no state).
• Deprecated React.createClass as the primary component definition method.
• Rewritten reconciliation algorithm for better diffing.

• Promoted best practices for maintainability and performance.
• Encouraged adoption of ES6 modules, destructuring, and arrow functions.

• Stateless components lacked defaultProps and propTypes support natively.
• React.createClass still required for mixins.

• React 0.13 revolutionized component architecture with first-class support for modern JavaScript syntax.

• Bug fixes for new JSX transform.
• Improved error messaging during render failures.

• Stabilized the migration path to ES6 classes and stateless components.

• Bugs when using ES6 class inheritance with custom prototype chains.

• Addressed core edge cases to enable confident adoption of the new patterns.

• Internal enhancements for React.cloneElement.
• Fixed incorrect behavior in nested component trees using refs.

• Strengthened composition and reuse mechanics.

• Refs still limited to class-based components.

• Improved low-level utilities for advanced patterns.

• Minor bug fixes in server-side rendering scenarios.
• Optimized mounting logic for deeply nested trees.

• Enhanced React’s SSR reliability.

• No full hydration or streaming SSR yet.

• Solidified React 0.13 as a stable base for modern client/server rendering.

React 0.13 was a transformational release that modernized how React developers architected components. It was the first version to truly embrace JavaScript’s ES6+ syntax and to decouple React from legacy patterns.

• ES6 Class Support: Modern, clean OOP-style components became first-class.
• Stateless Functional Components: Lightweight render-only components enabled more performant and declarative UI design.
• JSX Transform Improvements: Enabled simpler syntax with less boilerplate.
• Lifecycle Shift: Made it easier to think about components as declarative UI factories instead of class instances with mutation.

React 0.13 set the groundwork for everything from hooks to async rendering by promoting stateless purity and modularity. It remains one of the most important versions in React’s architectural evolution.

This document provides a deep technical overview of React v0.12.x, including all key releases. React 0.12 was a transitional version that modernized React's core principles and syntax in preparation for the more mature architecture in v0.13+.

React 0.12 introduced major syntax changes and cleaned up several legacy APIs. It also laid the foundation for composability, unidirectional data flow, and future integrations with ES6+ modules.

• Renamed React.renderComponent → React.render
• Better error messages and stack traces.
• Deprecated old patterns like getDOMNode() usage.
• Improved component naming for debugging.

• Simplified API (React.render) marked a move toward modern idioms.
• Prepared the community for more semantic and concise patterns.
• Better integration with developer tools.

• Still lacked support for ES6 classes and modules.
• Manual binding of this still required.

• A cleanup release that aligned API ergonomics with modern development standards.

• Minor bug fixes.
• Resolved performance regressions in component diffing.
• Improved error handling in JSX parsing.

• Stability improvements across JSX-heavy applications.

• JSX parsing still dependent on experimental Babel versions.

• Addressed early-adopter issues while preparing for v0.13’s structural shift.

• Better warnings for deprecated APIs.
• More consistent behavior for stateless render-only components.
• Enhanced behavior of refs.

• Paved the way for function components by refining render-only logic.
• Strengthened internal handling of component lifecycle assumptions.

• Did not yet introduce functional stateless components formally.

• A final polishing step before React's formalization of stateless component design in v0.13.

React 0.12 signified a semantic and structural shift in the React ecosystem. It broke away from old patterns, updated terminology, and introduced forward-looking API conventions.

• API Consistency: Renaming to React.render() aligned naming conventions with mental models.
• Tooling Focus: Enhanced error messages and stack traces improved debugging.
• Component Hygiene: Deprecated legacy accessors and patterns like getDOMNode().
• Preparation for Stateless Components: Built internal support for leaner component logic.

React 0.12 was more than a patch—it was a refactor of React's public surface, ensuring consistency and maintainability in the face of rapid community growth and ecosystem evolution.

This document offers a detailed, professional breakdown of React version 0.11, including all its patch releases. It highlights architectural decisions and prepares the ground for the shift toward React 0.12+.

React 0.11 marked a pivotal milestone toward React 1.0. It introduced refinements to the virtual DOM, better SVG support, and performance improvements. A focus on production-readiness and stronger alignment with the W3C spec made this version critical in React's evolution.

• Enhanced support for SVG and HTML5 DOM attributes.
• Improved event system and normalization.
• Initial support for context propagation through React.withContext.
• Better alignment with browser DOM standards.

• Allowed more seamless use of inline SVG.
• Improved developer control over non-standard DOM attributes.
• Foundation for context propagation pattern.

• Context API still experimental and verbose.
• Lack of stability in prop-type enforcement for complex objects.

• React 0.11 moved React closer to real-world production readiness and platform alignment, while enabling component reuse across SVG and HTML.

• Bug fixes and memory leak patches.
• Minor improvements in diffing behavior.
• Better warnings for invalid DOM nesting.

• Better dev ergonomics and reduced runtime surprises.

• Still lacked comprehensive developer tooling.

• Stability release to prepare for upcoming architectural improvements.

• Performance improvements to shouldComponentUpdate.
• Refined internal reconciliation behavior.
• Better support for escaping and sanitizing content.

• Helped optimize large component trees.
• Improved security and render fidelity.

• Internal APIs still exposed edge-case bugs under high load.

• A solidifying step to make React scalable and secure in real-world apps.

React 0.11 represented a shift in mindset from a developer experiment to a reliable, production-ready UI engine. Key takeaways:

• Platform Compatibility: Focused on aligning React's DOM diffing and rendering logic with HTML5 and SVG specifications.
• Context Foundation: Laid the groundwork for future context API usage.
• Security Focus: Introduced mechanisms to sanitize rendered output, critical for XSS mitigation.
• Performance Awareness: Improved lifecycle handling, paving the way for Fiber in future versions.

React 0.11 marks the version where React's internals matured significantly, proving that virtual DOM could handle not just toy examples but large-scale apps. It became the precursor to architectural decisions that would later lead to React 15+ and React Fiber (v16).

The early versions of React—spanning v0.3.0 (May 2013) to v0.10.0 (March 2014)—represent the foundation of modern declarative UI development. These releases established React’s core principles, introduced radical ideas like the Virtual DOM, and laid the groundwork for component-based architectures that would later dominate frontend engineering.

• Introduced JSX: A novel syntax that blended HTML-like tags with JavaScript logic.
• Virtual DOM Concept: Enabled efficient diffing and updates to the real DOM.
• Component Model: Encouraged encapsulation and reusability.

• PropTypes & DefaultProps: Brought runtime type checking and default property values.
• Comment nodes & DOM tweaks: Improved real-world rendering fidelity.
• React.Children utilities: Enhanced component composition patterns.

• Lifecycle methods like componentWillMount() emerged.
• Better control of input fields and form synchronization.

• Broader support for HTML5 & SVG attributes (e.g., rows, cols, autoCorrect).
• DOM attributes, crossOrigin, and sandbox support added.
• Immutable Update Utilities: React.addons.update() introduced in v0.10.0.
• Early performance improvements through smarter shouldComponentUpdate.

• Design Philosophy: Even before reaching v1.0, React’s focus on composition, reactivity, and declarative rendering set it apart from template-based frameworks of the time.
• Risk & Reward: JSX was controversial in 2013, but its eventual widespread adoption proved React’s bet on developer ergonomics was correct.
• Legacy Value: These versions inform today’s API design—patterns like controlled components, one-way data flow, and immutability were introduced here.

• React 0.x wasn’t just an experiment—it was a radical redefinition of UI development.
• While lacking advanced features (Hooks, Suspense, SSR), these versions established principles like unidirectional data flow, composable components, and declarative rendering.
• Understanding this era gives developers a deeper appreciation for the architectural stability and foresight that powers modern React.

• First public release.
• JSX syntax.
• Virtual DOM and React.createElement().
• Component-based design.

• Introduced functional and class components.
• Manual state management via this.setState().

• No lifecycle hooks beyond basic mounting.
• No ecosystem.

• Foundation for declarative UIs in JavaScript.

• Minor bug fixes.
• Performance improvements.
• Internal refactoring.

• Stability upgrades.

• Still early-stage experimental.

• Introduced PropTypes for type checking.
• Default props (getDefaultProps).
• Comment nodes support.

• More robust validation & developer guidance.

• No server-side rendering.
• Limited event support.

• Early push toward developer tooling and DX improvements.

• Introduced React.Children utilities.
• Input value tracking.
• Lifecycle method componentWillMount().

• Performance optimization for controlled inputs.

• Expansion into form handling and component composition.

• Inconsistent reconciliation with text inputs.

• Significant move toward interactive UI components.

• DOM property support expansion (e.g., rows, cols, autoCorrect).
• Added event support (onContextMenu).

• Increased HTML5 compatibility.

• Still lacked cross-browser consistency.

• Emphasized HTML fidelity and compatibility.

• Added more attributes (crossOrigin, sandbox, scope).
• PropTypes.shape() for nested prop validation.
• Better React.withContext()

• Advanced validation and structure control.

• Verbose context handling.

• Push toward maintainable, large-scale apps.

This document provides a detailed breakdown of React versions prior to v0.11, covering their features, changes, and architectural significance. Each version includes key features, what was added compared to the previous version, limitations, and expert-level insights.

• srcSet support for responsive images.
• First appearance of React.addons.update() for immutable-style state updates.

• Foundation for responsive rendering and immutability.

• No support for hooks or async rendering yet.

• Setup for declarative data management and device support.

• v0.3.0: Initial architecture and syntax (JSX, Virtual DOM).
• v0.4.x: Developer guidance improvements (PropTypes).
• v0.5.x: Composition and form control.
• v0.8.x: DOM and event compatibility.
• v0.9.x: Component data structure and context fidelity.
• v0.10.x: Responsive rendering + immutable data update utilities.

These early versions laid the groundwork for React's scalability and developer experience, including its eventual dominance through features like hooks, concurrent rendering, and compiler-assisted reactivity.

Understanding React’s documentation lifecycle is critical for:

• Maintaining long-lived production systems
• Migrating between major versions
• Accessing accurate legacy behavior (especially pre-hooks/class-based architecture)

• React emphasizes stability and long-term support by maintaining versioned docs.
• React’s versioned documentation enables teams to:
  • Use the right resources for their app’s version.
  • Upgrade incrementally while preserving context-specific references.
  • Avoid confusion between breaking and non-breaking changes.

Always reference the correct subdomain (x.react.dev) for historical versions when debugging or planning migrations.