There are several tools available that can be used to develop the front end of a website, and understanding which tools are best fit for specific tasks marks the difference between developing a hacked site and a well designed, scalable site.
Here is the short list of the technologies in which we work.
React is a library for building composable user interfaces. It encourages the creation of reusable UI components, which present data that changes over time. Lots of people use React as the V in MVC.
We also use few more technologies/frameworks to create the UI/UX and make it more responsive like HTML, CSS, Twitter Bootstrap, Jquery UI.