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digital image sizes
• digital image sizes
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adding images to documents
• position
• cropping
• enhancement
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image file types
• jpg or gif
• transparency
screen prints and clip art
• screen prints
• clip art
the problems with text
• fonts
• line length
• emphasis
• text boxes
• text images
free tools
• text
• drawing
• image editing
• web page design

If you're dealing with large, professional images for printing then you'll probably have expensive software like Adobe Photoshop, Quark and the like and will know all about this already.

This is for those who aren't and don't, who will really only need to know about three types of image file: jpgs, pngs and gifs.

As a general rule, use gifs for illustrations, clip art, and images with large areas of flat color, use jpgs for photographs and images with continuous tones.

In your image editor you will usually be asked to choose between the two when saving or exporting. If 'saving' do remember to keep the original unchanged, probably by 'saving as . . .' and use a different name for the adjusted version!

It won't help your images look any better but you might like to know that jpg (or jpeg) stands for Joint Photohraphic Experts Group. Gif stands for Graphics Interchange Format. The comparatively new kid on the block is png - Portable Network Graphics. This format can be suitable for either photos or graphics and is particularly good where you have text on a background. It also supports transparency so images don't have to have four corners and is good for irregularly cropped photos. Gif images are usually quite low resolution (how tightly dots of colour are fitted to make up an image) and may be unsuitable for printing so png can be better for that too. Basically, when you've made changes to, or created an image, you'' either 'save as . . ' or 'export as . . .' one of these three types and should be able to preview what each will look like. So experiment, keeping an eye on file sizes which should be displayed for each.

If the image is likley to be displayed on the web then remember also that there are currently only 216 colours available. This is the Windows palette. (The Mac one is slightly different).