Understanding File Types
There are hundreds of different file types, and understanding which one to use can be difficult. To help, we've compiled a little cheat sheet to help you familiarize yourselves with the most common file types.
This is the most common file format found online. JPEGs are really great for online images because they compress really well. This leads to a smaller file size, and faster page loads. One thing to note, JPEGs aren't always good for sharp edges or text--they may come out a bit blurry.
Tiff's are really good for print images. They are really large file sizes because they hold a lot of color and detail information. Not very good for websites.
PNGs can only be used online. These images compress really well and unlike JPEGs, they work great for sharp edges, text, and transparency. One thing to note: This is a relatively new file type, and isn't compatible with all applications and platforms (for example, Internet Explorer 6 or lower versions.)
Gif's compress really well, so they're good for online. But they don't hold nearly as many colors as JPEGs or PNGs, so they're better for text and graphs rather than photos and logos. They work really well with sharp edges and text.