JavaScript is a loosely typed language. That means you do not have to specify the data type of a variable when you declare it, and data types are converted automatically as needed during script execution. So, for example, you could define a variable as follows:
var answer = 42
And later, you could assign the same variable a string value, for example,
answer = "Thanks for all the fish..."
Because JavaScript is loosely typed, this assignment does not cause an error message.
In expressions involving numeric and string values, JavaScript converts the numeric values to strings. For example, consider the following statements:
x = "The answer is " + 42
y = 42 + " is the answer."
The first statement returns the string "The answer is 42." The second statement returns the string "42 is the answer."
