GIF is one of the most common raster image formats. Its name is an abbreviation for Graphics Interchange Format File. The developer is the CompuServe organization. A feature of this particular image format is its ability to support the animation function. You can edit animated GIFs in different programs (for example, Easy GIF Animator). Animation is achieved due to the fact that a file of this format carries in itself in a certain sequence several raster images at once. With a depth of up to 256 colors, significant data compression in GIF files is possible without loss of quality.
PCX is one of the first bitmap image formats developed by ZSoft for the PC Paintbrush program. This is the original bitmap format for the DOS / Windows platform. It supports monochrome single-bit black and white images, an eight-bit gray scale, indexed color images, and full-color 24-bit RGB model images. But there is no support for additional color and alpha channels, clipping paths, color management. The format provides for the application of the simplest compression algorithm (RLE) so that information is not lost. Now it has a purely historical significance. The PCX file format has been replaced by newer image formats. However, the format is still used in separate applications in order to scan and send faxes. PCX multi-page fax documents use the .DCX extension. Most DOS-based programs are suitable for viewing PCX (PC eXchange) files. In particular, the viewer Norton Commander. The big drawback of the PCX format is that it has too many versions. This can be explained by the fact that the PCX standard is open, and therefore it has been widely used by most independent software developers. And therefore it is constantly updated.