WebCore is a layout, rendering, and DOM library for HTML and SVG developed by the WebKit project, originally developed by Apple as a fork of KHTML. It is licensed under the LGPL. The WebKit framework wraps WebCore and JavaScriptCore, providing an Objective-C application programming interface to the C++-based WebCore rendering engine and JavaScriptCore script engine, allowing it to easily be referenced by Cocoa-based applications; later versions also include a cross-platform C++ platform abstraction, and various ports provide additional APIs.
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basically it has to update and restart so that all cocoa based apps can use the new version.
WebCore is a layout, rendering, and DOM library for HTML and SVG developed by the WebKit project, originally developed by Apple as a fork of KHTML. It is licensed under the LGPL. The WebKit framework wraps WebCore and JavaScriptCore, providing an Objective-C application programming interface to the C++-based WebCore rendering engine and JavaScriptCore script engine, allowing it to easily be referenced by Cocoa-based applications; later versions also include a cross-platform C++ platform abstraction, and various ports provide additional APIs.
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basically it has to update and restart so that all cocoa based apps can use the new version.