Reactjs
With react, we don’t need to load a new page to change the content, instead, we can use javascript through react to change the data that’s visible on the screen. This is making smooth UI and a better user experience. React focuses on component things and don’t have other built-in features. If we need other features we have to bring 3rd party packages. So developers describe it as a JS library instead of a complete framework. A ReactJS application is made up of multiple components, each component responsible for outputting a small, reusable piece of HTML code. React uses a new mechanism of updating virtual DOM instead of reloading complete DOM every time. Behind the scene react engine keep on comparing real DOM and virtual DOM, and if find some difference it updates the virtual DOM just as a patch. Thus, it does not create DOM repeatedly and results from there is no unnecessary memory wastage and reduction of performance. ReactJS still used the same traditional data flow, but it is not directly operating on the browser's Document Object Model. The React Virtual DOM exists entirely in memory and is a representation of the web browser's DOM. Due to this, when we write a React component, we did not write directly to the DOM; instead, we are writing virtual components that react will turn into the DOM.