I have this code that filters an array using the .filter method. 
I'm extremely confused about the function's parameters that is being specified in the .filter method. 

Where does the parameter come from? How do I know when to add a parameter like 'value', and what is the value of the parameter 'value'?

```
var newArray = [1,2,3,4,5,6,7,8,9,10];

    newArray = newArray.filter(function(value) {
      return value < 6;
    });

```

I'm not too sure if it is the right term to use.