BMP (BitMaP): BMP files are a standard format for Windows 3.0 and later (for example, Windows wallpaper uses BMP images). While still commonly used, BMP files are too large for Web use, and have been supplanted by other formats for use in high-quality graphics.
GIF (Graphics Interchange Format): This is pronounced either "Jif" or "Gif" (with a hard G), depending on where you heard it first. GIFs are also widely used for Web site graphics. However, this format only uses 8-bit color (in other words, up to 256 colors), as opposed to JPEG's 24-bit color capacity. As a result, it is usually recommended that simpler graphics, such as charts, be saved as GIF files, while photographs should be saved as JPEG files.
JPEG (Joint Photographic Experts Group): Usually pronounced Jay-Peg, this is a popular compression standard that provides relatively little perceptible loss in image viability. JPEG is used a great deal for Web site graphics; it is also useful for emailing photos or other images.
PNG (Portable Networks Graphics): A relatively recent development, PNG offers good compression and 48-bit color. With JPEG and GIF, it is one of the three formats most suitable for Web sites, and in fact is expected to eventually replace GIF. It is not yet as popular as the other formats, however.
TIFF (Tagged Image File Format): is a very widely used format that that handles a wide variety of image types, including monochrome, grayscale, and 24-bit color. TIFF files offer high-quality images, but TIFF files tend to be large (although there are several compression methods available). As a result, while TIFF files are suitable for high-quality photo and other images, but cannot be used for Web sites (and should not be sent via email, if possible).
