Modern JS should be written in strict mode which bans implicit globals (preferring to explicitly declare them at the top level instead, thus prevent accidental globals when a variable name is typoed). Yes, you should always use var .
The latest ECMAScript(ES6) standard defines seven data types: Out of which six data types are Primitive(predefined). Numbers: 5, 6.5, 7 etc. String: “Hello GeeksforGeeks” etc. Boolean: Represent a logical entity and can have two values: true or false.
How do you declare variables?
To declare (create) a variable, you will specify the type, leave at least one space, then the name for the variable and end the line with a semicolon ( ; ). Java uses the keyword int for integer, double for a floating point number (a double precision number), and boolean for a Boolean value (true or false).
- Writing into an HTML element, using innerHTML .
- Writing into the HTML output using document.write() .
- Writing into an alert box, using window.alert() .
- Writing into the browser console, using console.log() .
How do you print a variable in console?
How do you print a variable in HTML?
- Display the variable using document. write() method.
- Display the variable to an HTML element content using innerHTML property.
- Display the variable using the window. alert() method.