How to make a transparent JPG?

How do I create an icon in JPG or some other format that actually has a transparent background—meaning you can see whatever is underneath it? I want to be able to slap it onto a document or another image so that only the logo letters show up and the background stays clear, letting the image or text below peek through. It’s supposed to work like the Aero effect in Vista. I managed to get it looking right in Microsoft, but the second I try to save it as a JPG or any other format, it just saves the whole thing with a solid, opaque background. 😕

Not sure if JPG even handles transparency. You're better off trying a GIF, that should work for sure. (hopefully you don't have like a million different color shades in there)

The issue is that JPG doesn't actually support transparency, so you'll really need to switch over to a PNG format to make that work.

Alright, look—you can't do this with a JPG since you need transparency. You’ll have to go with a GIF if you want that background to stay clear. But the real question is how you actually export it. I'm talking about taking a specific word—let's say "signature"—and overlaying it onto different photos or blocks of text while keeping the letters visible and the background completely transparent. 🙄

First, you just fire up Photoshop, head over to the File menu, select New, and then make sure you set the background contents to transparent.