Ionic framework is an open-source UI toolkit for building performant, high-quality mobile apps, desktop apps, and progressive web apps using web technologies such as HTML, CSS, and JavaScript. It allows developers to build once and run everywhere.

The Ionic framework mainly focuses on front-end user experience or UI interaction, which handles all the look and feel of your app. It is easy to learn and can integrate with other libraries or frameworks such as Angular, Cordova, etc. It can also be used as a standalone without a front-end framework using a simple script include.

Officially, the Ionic framework has integration with Angular, but it also provides support for Vue.js and React.js, which are in development.

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