This file format with shortcut EPS means Encapsulated PostScript. It is document of PostScript. We can classify it as graphical format, its main advantage is use of vector graphics, its extension is .eps, but there are also two another extensions - .epsf and .epsi. Its use is big due to ability to compose one picture over another. Also this format is creating its own miniature that is used for showing.
To view files saved in format EPS you can use one of tens of programs. First of all there are Adobe programs – Adobe Acrobat, Adobe Illustrator, Adobe Indesign or Adobe Photoshop. All of them can view these files and moreover they can create files in EPS file type. Next program, which is very similar to them Is application GIMP, which require plugin called Ghostscript for good functionality of this program. So the default program for opening files in this format is GIMP.