This is worth getting your head around just for the console.

<this post is partially for those of you who are, like me, relatively new to javascript. If you're one of the demigods that works at twitter/facebook, go ahead and ignore this>

I've been transitioning all of my projects from python cgi scripts (yuck), to shtml files, javascript clients, and APIs that run on node.js.

For somebody like me, that has been writing python+cgi for the last 5 years, diving into javascript was daunting. Terrifying even.

Console made this a lot, lot, lot easier. In javascript, you can call

    console.log("thing") 

and it will print it out to the console (again, this is obvious if you're done any JS development, I'm sure).

But that isn't all...

Suppose that I'm working with an object called map_pins. In the javascript console, I can just type:

    map_pins;

and it will print out the object for me in a tree that I can traverse by clicking the little sideways triangles.

Very, very nice.

I can also interact with my javascript functions from the console. If I have a function called update_bounds(), I can force it to fire from the console by just typing:

    update_bounds()

This is really, really nice. Before I discovered this, my javacsript was full of alert("I made it to this without crashing");

It was awful.

If you're learning JS and OP's article looks over your head, at least take the console away from it.