How come you can put a number inside of a string with Javascript? can you give another example of how this works?

In your example, the number variable is not in quotes. There are quotes around the bracket ('['), and there are quotes around the ending phrase that includes the closing bracket (' questions left]').

When the JavaScript system sees that the numeric variable questions is being concatenated (+) with two strings, it performs what's known as type coercion, taking whatever value it holds and creating a string that represents that value.

So, the whole process goes like this:
'['     start with this string
+ questions     convert questions to a string and concatenate it
+ ' questions left]'     then concatenate this string
var questionsLeft =     finally put the new string into the variable questionsLeft

I hope that clears it up a bit.

-sp

Oh, now it makes sense. I was looking at the quotes all wrong. So when Dave said at a point that Javascript allows you to put a number inside a string he meant inside the whole string, no? Thank you!