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This -TypeScript- introduction is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License

As a superset of JavaScript in general and JavaScript 6 in particular, TypeScript provides code, which wraps up JavaScript code. Additional incompatible code creates type checking matter used by the TypeScript compiler. The TypeScript transpiler next erases this incompatible code so that generated JavaScript code is interpretable by Web browsers on the front-end side and Node.js on the back-end side.

TypeScript in a nutshell