Learning the Basics of Windows (Part One)

To most, a window is a window.  When I first came aboard I was vaguely aware there were different types, but that was about it.  Although Marvin offers pretty much endless options when you get into the details, there are a few basic window types;
Double Hung. 
I've heard that about 60% of the double hung windows made are in the Northeast.  I find that number a little low, but maybe that refers to new windows -not existing inventory.  If you've never heard this term, it refers to the fact both of your sash's (the pieces holding the glass) move up and down.  Doesn't have to move easy or well, they just move if you try hard enough.  Very basic window prevalent in our area.
Single Hung.  Looks the same as a double hung, only the top sash is stationary.

Casement: 
 
This is what I used to refer to as the "cranky kind".  I've since stopped.  These are more popular on the west coast and actually the most efficient type of window since the outside weather/wind only pushes it closed more tightly.  Usually you see 2 side by side and there is a crank mechanism that opens it to the outside along the jam like a book.  Not great for retail locations opening over sidewalks, as people could waltz right into them.  Marvins' Ultimate Casement windows have wash-mode hardware that lets you basically swivel them so the outside is in, allowing easy access to clean the upper floor windows from the inside.
Awning. 
This window also has a crank mechanism that opens it to the outside, only it raises up along its' top edge.  Popular in basements where there are shorter, wider windows.  Little tid-bit for you, the amount the window will open is half it's width.