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Introduction to JavaScript

Review

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

  • Data is printed, or logged, to the console, a panel that displays messages, with console.log().
  • You can write single-line comments with // and multi-line comments between /* and */.
  • There are 7 fundamental data types in JavaScript: strings, numbers, booleans, null, undefined, symbol, and object.
  • Numbers are any number without quotes: 23.8879
  • Strings are characters wrapped in single or double quotes: 'Sample String'
  • The built-in arithmetic operators include +, -, *, /, and %.
  • Objects, including instances of data types, can have properties, stored information. The properties are denoted with a . after the name of the object, for example: 'Hello'.length.
  • Objects, including instances of data types, can have methods which perform actions. Methods are called by appending the object or instance with a period, the method name, and parentheses. For example: 'hello'.toUpperCase().
  • We can access properties and methods by using the ., dot operator.
  • Built-in objects, including Math, are collections of methods and properties that JavaScript provides.
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