If you're in a function, you can always refer to `this`. But what is it?

It can be anything. It represents the context that the function should be executed against. Ultimately, whoever called the function has control over what it is. There are some defaults though. For example, if the function is the value of a property in an object (a method), `this` takes on the value of the object:

```
var myObj = {
     func: function() {
          console.log(this); //logs myObj
     }
}
```