1) Any changes made in Angular may require Browser DOM to be rerendered completely, which could make your application slow, but in case of React js, Virtual DOM is created out of the component's render element, which compares two versions of Virtual DOM and just changes the specific part which has changed in JSX and updates, also has a key property while looping through array, which just reorder's any element which has unique key value instead of rerendering whole data. 2. React uses JSX, where we can combine both HTML and Javascript into View, that allows us to use few of iterable methods in a component. 3. React supports Modular Programming which makes us to divide our application into several Components, and those could be reusable though using HOC concepts. 4. React js provides various component life cycle methods which makes us to optimize our application by using component life cycle methods effeciently. 5. Angular js uses directives attributes on elements which could make us difficult to maintian in case of large scale applications. 6. React js uses inline styling. 7. Angular js is a complete framework, where as React js is a javascript library and acts as a view part of MVC.