Overview. This is an HTML tutorial explaining about cross-platform images suitable for use in a Web document and also an explanation about image transparency. Resources are given for the image software and the Related Links."

The format of an image to be used on the Web should be a file type that is "cross-platform" which means that several types of operating systems can use that file type. Platforms are operating systems and system configurations such as a Macintosh running OS X on the G4 with dual processors, a PC running Windows XP, or another computer running the Linux operating system. Your images will need to be in a format that all of the computers operating on the Web can use. Popular file formats for Web use are the GIF and JPEG file formats. All graphical browsers support GIF and JPEG file formats.  PNG file formats can only be recognized by some of the graphical browsers but not all of them.

TRANSPARENCY. Transparency is a term used to indicate a GIF89a format file in which a selected color is "taken out" of the graphic file when displayed, so that the browser background shows through the image making the image appear to "float" on the screen.   JPEG files do not support transparency nor do GIF87a images.

Creating and manipulating images requires drawing or graphics programs and tools. Paint Shop Pro,  Adobe Photoshop  and Adobe Illustrator are used by Web designers.

Windows users can use  Paint Shop Pro, Adobe PhotoShop,  CorelDraw  and other graphics programs.

Macintosh users: Adobe PhotoShop is available for the Macintosh computer and Quark Express is another publishing and photo editing program for the Mac.

Unix platform developers can use the program called xv developed by John Bradley. This program handles the file formats of GIF, PM, PBM, XBM, RAS, JPG, and TIF and translates them into other file formats (the same as listed, plus PS).

The following list contains several of the image formats and one to trick you. Find the fake one. I have used .GIF , .JPG and .BMP images on Web pages.