Babel is a transpiler, which is a kind of compiler that processes the source code. Here, the input and output code are at a similar level of abstraction, e.g. JSX to Javascript, unlike in a regular compiler, where higher-level code, e.g. Java, is converted to lower-level code, e.g. Assembler or just machine code. Thanks to the Babel transpiler, you can use JSX (JavaScript XML) notation in Virtual DOM, which is modeled on XML. Babel transposes (rewrites) the JSX code to Javascript, as well as the newer Javascript syntax to the older one to support more browsers. Therefore, it enables more convenient, readable and faster component creation in React, and also ensures backward compatibility.

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