Why Can't I Save This?

So you're making this fabulous creation and you now want to save your work, but it won't let you, you get an error.  You ask yourself "why can't I save an image with Gimp?" and you get frustrated.  Well, Gimp is a little different than Photoshop when it comes to saving.  It gives you drop down options of where to save but not how to save.  The answer is really simple:  when you save, you also have to save the extension.  If you want it as a jpeg, you save as title.jpg, as a png you save as title.png, same for gif, psd (photoshop document), or xcf (gimp version of a psd), etc.  Simple but not obvious.  Does that help? Yay!! LOL =)