EPS means Encapsulated PostScript. It is the file format based on the PostScript language. It was designed by Adobe Company. This format has been used earlier as the base for AI (Adobe Illustrator) extension. Nowadays it uses as graphics transporting method. Besides, EPS data can be embedded into another PostScript object.
This format is assuming as a vector as raster graphics. It can also include a combination of raster and vector elements. The format is using in the polygraphic industry. An output product could be processed only by the PostScript device. EPS format hasn’t the support for transparency images. However, it supports almost all color models as RGB, Grayscale, Lab, CMYK, and Multi-channel.
If you want to open EPS files, you should use complex graphics programs as Adobe Illustrator, Photoshop, QuarkXPress or CorelDraw. Freeware editors usually can only view EPS files. For example, IrfanView can open and view EPS file if you will install a special plugin (Postscript.dll). So, you have to use trial or full versions of powerful graphics editors if you want to work with EPS files. If you are not a professional designer and want to view an EPS file, you should pay attention to IrfanView.