Question about defining variables

I'm fairly new to arduino, but have done some parallax basic stamp hobby projects in the past.
One thing that I am having a bit of trouble wrapping my head around is how to properly define a numeric variable.

In the basic stamp world, because of limited program space, you had to be careful about how you defined the size of a variable to conserve resources.
So, I'm used to thinking about when I would want to use a bit, nibble, byte, or word.

But in arduino, all i see in most samples, and most posts, is the usage of int.

What am I missing here?
Is it not necessary to worry about when to define a variable as a bit, nibble, byte or word?

Is it not necessary to worry about when to define a variable as a bit, nibble, byte or word?

same as anything else, if your concerned about memory useage you need to use the proper type, you can see all the different types available to you ...

why does all the examples use int? its easy and you dont really need 2k to blink a LED, but if you are considering larger projects its better to get in the habit of knowing whats available