What do you mean by TypeScript?
TypeScript is created by Microsoft, a typed superset of JavaScript which adds the optional types, async/await, classes including several other features and then compiles to the plain JavaScript. Angular is entirely built in TypeScript and is being used as a primary language.
TypeScript can be installed globally as,
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The AngularJS uses JavaScript while the Angular2 and its above version uses the TypeScript, which is basically the superset of JavaScript.