An overview of JavaScriptCommentsVariablesConstantsNumberStringUndefined valuesBooleansThe instanceof operatorDate objectsThe + operatorThe ++ and -- operatorsBoolean operatorsEqualityStrict equality using ===Weak equality using ==JavaScript typesAutomatic semicolon insertionJavaScript style guideWhitespacesParentheses, line breaks, and bracesQuotesEnd of lines and empty linesType checkingType castingConditional evaluationNamingThe eval() method is evilThe strict modeEnabling the strict mode for an existing code can break itPackage with careVariables must be declared in strict modeThe eval() function is cleaner in strict modeFeatures that are blocked in strict modeRunning JSHint