Blink (browser engine)

Blink (browser engine). Blink is a free and open-source browser engine developed by the Chromium Project as part of the Google Chrome web browser. It is a fork of the WebKit engine's WebCore component, initiated by Google to facilitate a more rapid and independent evolution of the core web platform. The engine is now the foundational rendering and layout software for a vast majority of the world's web browsers, powering Google Chrome, Microsoft Edge, Opera, and many other applications built on the Chromium codebase.

History and development

The development of Blink was announced on April 3, 2013, by Google engineers, including Adam Barth and Eric Seidel, as a fork from the WebKit repository. This decision was driven by the desire to reduce complexity in the codebase by removing unnecessary components like the WebKit porting layer and to allow for more aggressive architectural changes. The initial code was based on the WebCore component of WebKit, which itself had roots in the earlier KHTML engine from the KDE project. Key figures in its early stewardship included Google's Linus Upson and Sundar Pichai, who oversaw the Google Chrome project. A major milestone was the integration of Blink into the Chromium browser, with its first stable release appearing in Google Chrome version 28 in July 2013. The project is governed by the Chromium Project's decision-making process, involving contributors from multiple companies like Microsoft, Opera Software, and Intel.

Architecture and components

Blink's architecture is modular, designed for high performance and security across diverse platforms. Its core components include the DOM, CSS engine, and JavaScript engine, though it delegates JavaScript execution to the separate V8 engine developed by the Chromium Project. A critical architectural feature is the multi-process model, which isolates individual browser tabs and plugins into separate processes to enhance stability and security. The engine implements the HTML, CSS, and Web APIs specifications, with rendering handled through compositing layers managed by the Skia Graphics Engine. Key internal modules include the Style Engine for CSS resolution and the Layout Engine for calculating element positions.

Features and standards support

Blink is known for its rapid implementation of emerging web standards, often serving as a testbed for new features before they are standardized by the W3C or the WHATWG. It provides extensive support for modern CSS features like CSS Grid Layout, Flexbox, and CSS Custom Properties. The engine also implements advanced JavaScript APIs such as WebAssembly, Service Workers for offline functionality, and the Web Components suite. It was an early adopter of the QUIC transport protocol, which later evolved into HTTP/3. Support for multimedia is robust, encompassing the WebRTC protocol for real-time communication and various HTML5 video and audio codecs. Its development process is closely aligned with the Chromium's release cycle, allowing for frequent updates.

Usage and adoption

Blink is the most widely used browser engine in the world, dominating global market share. Its primary implementation is in Google Chrome, which holds the largest single-browser user base. Following a major strategic shift, Microsoft adopted Blink for its Microsoft Edge browser in 2019, abandoning its legacy EdgeHTML engine. Similarly, Opera Software transitioned from its Presto engine to Blink in 2013. The engine is also the foundation for numerous other Chromium-based browsers like Brave and Vivaldi. Beyond traditional browsers, Blink is embedded in many Electron-based desktop applications, such as Slack and Microsoft Teams, and powers the webview components in Android and Google ChromeOS.

Relationship with other engines

As a fork of WebKit, Blink shares a common ancestry with the engine that powers Apple's Safari and GNOME Web. However, the codebases have diverged significantly since 2013, with each implementing different features and optimizations. Blink's main contemporary competitors are Gecko, developed by the Mozilla Foundation for Mozilla Firefox, and WebKit, as maintained by Apple. The engine ecosystem also includes lesser-used projects like Goanna. Despite competition, engineers from companies like Google, Microsoft, and Apple often collaborate on web standards bodies like the W3C. The relationship with V8 is symbiotic, as Blink provides the DOM and rendering while V8 executes JavaScript.

Category:Browser engines Category:Chromium (web browser) Category:Free software programmed in C++ Category:Google software Category:Software forks