HTML5 is a language for structuring and presenting content for the World Wide Web, and is a core technology of the Internet originally proposed by Opera Software. It is the fifth revision of the HTML standard. wikipedia.org

Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation (that is, the look and formatting) of a document written in a markup language. wikipedia.org

React is an open-source JavaScript library for creating user interfaces that aims to address challenges encountered in developing single-page applications. wikipedia.org

Node.js is a software system designed for writing highly-scalable internet applications, notably web servers. Programs are written in JavaScript, using event-driven, asynchronous I/O to minimize overhead and maximize scalability. wikipedia.org

"Express is a minimal and flexible Node.js Web application framework, providing a robust set of features for building single-page, multipage, and hybrid Web applications"

MongoDB is an open source document-oriented NoSQL database system written in the C++ programming language. It manages collections of BSON documents. wikipedia.org

JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles. wikipedia.org

"TypeScript is a free and open source programming language developed and maintained by Microsoft. It is a strict superset of JavaScript, and adds optional static typing and class-based object-oriented programming to the language. Anders Hejlsberg, lead architect of C# and creator of Delphi and Turbo Pascal, has worked on the development of TypeScript." wikipedia.org