console.log the data type in js code example

Example 1: type of javascript

//typeof() will return the type of value in its parameters.
//some examples of types: undefined, NaN, number, string, object, array

//example of a practical usage
if (typeof(value) !== "undefined") {//also, make sure that the type name is a string
  	//execute code
}

Example 2: javascript check type of variable var

> typeof "foo"
"string"
> typeof true
"boolean"
> typeof 42
"number"