There's even more to TypeScript

TypeScript by itself has a number of other benefits:

• It is a superset of JavaScript: All JavaScript programs (for example, ES5 and ES2015) are already valid TypeScript ones. In essence, you have already been writing TypeScript code. Since it is based on the latest version of the ECMAScript standard, it allows us to take advantage of the latest bleeding-edge syntax provided by the language.
• It supports optional type checking: If, for any reason, we decide that we don't want to explicitly define the type of a variable or a method, we can just skip the type definition. However, we should be aware that this means we are no longer taking advantage of the static typing, so we are giving up on all the benefits mentioned earlier.
• It is developed and maintained by Microsoft: The quality of the implementation of the language is very high, and it is unlikely that support will be dropped unexpectedly. TypeScript is based on the work of some of the world's best experts in programming language development.
• It is open source: This allows the community to freely contribute to the language and suggest features, which are discussed in an open manner. The fact that TypeScript is open source makes the development of third-party extensions and tools easier. This extends the scope of its usage even further.

Since modern browsers do not support TypeScript natively, there is a compiler that translates the TypeScript code we write into readable JavaScript in a predefined target version of ECMAScript. Once the code is compiled, all the type annotations are removed.