JavaScript in 30 words
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JavaScript Function Expressions Explained Simply

Functional expressions load only when the interpreter reaches that line of code. They're not hoisted, allowing them to retain a copy of the local variables from the scope where they were defined. They do not polute the global scope.

const formatLesson = function (number, title) {
  return number + ". " + title;
};

console.log(formatLesson(1, "Variables"));
console.log(formatLesson(2, "Functions"));

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