Many computer software programs and operating systems can be downloaded from the internet in the form of an ISO image. An ISO image is basically a CD or DVD converted to a single file, which can be returned to CD form through a process known as "burning."
Burning ISO images to a CD or DVD is a fairly straight-forward process. There are many programs and applications that can be used to get the job done, some free and others not. If you don't already have a preferred image burning application, NeoSmart Technologies recommends using ImgBurn as a free & reliable solution.