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Introduction to JavaScript

Review Types and Operators

Let's take one more glance at the concepts we just learned:

  • Four essential data types in JavaScript include strings, numbers, booleans, and null.
  • Data is printed, or logged, to the console with console.log().
  • Four built-in mathematical operators include +, -, *, and /.
  • JavaScript associates certain properties with different data types.
  • JavaScript has built-in methods for different data types.
  • Libraries are collections of methods that can be called without an instance.
  • You can write single-line comments with // and multi-line comments between /* and */.
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