With console.log('setter called: ${owner}'); what are the $ and curly bracket for?

Hi there! The dollar sign and the curly brackets are part of a "new-ish" type thing in JavaScript called a JavaScript Template Literal. They are really nice to use, and I highly recommend learning about them. Treehouse has a 9-minute workshop on them and I can almost guarantee it's worth your time. Take a look at it here.

But for a small example, consider this code:

var x = 10;
var y = 20;

If I then wanted to do a console.log() to print out the results of the multiplication of those two numbers, I could do either:

console.log("The product of " + x + " and " + y + " is " + x * y);

Or I could do this:

console.log(`The product of ${x} and ${y} is ${x * y}`);

In both cases, the following string will be logged to the console: The product of 10 and 20 is 200. But take a look at how much the JavaScript Template literal simplifies all the concatenation and makes your code look cleaner.

Hope this helps!