What Is Power ISO?
 
A variety of programs are capable of editing, mounting and burning ISO files. PowerISO is one of them. Such programs can be handy when dealing with ISO files because of their flexibility in dealing with ISO files. PowerISO is one of the few such programs that is not free.
 
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PowerISO deals with virtual CDs and DVDs.ISO files

An ISO file is a virtual CD or DVD; that is, a representation on your hard drive of data intended to be copied to disk. Such images are commonly used to provide exact replicas of video DVDs (sometimes legally, sometimes otherwise) or versions of the Linux operating system (a free alternative to Windows or Mac OSX.) These images can easily be distributed online and quickly burned by end users, ensuring CDs distributed on the Internet and burned are all exact replicas.

ISO files represent an open standard established by the International Standards Organizations (ISO---get it?) in 1987. This means anyone can use the standard in software, provided they comply with the official standards.

PowerISO: What it is

Power ISO just one of many pieces of software capable of creating and using ISOs files. The program can create ISO images using a CD or DVD as a source, burn ISO images to a CD or DVD and even mount an image on your hard drive in such a way that your computer will think the CD is in your drive. This allows you to access the files without burning the ISO to disk.

PowerISO is available only for the Windows family of operating systems. Linux and Mac users need to look elsewhere for such functionality, though most of these functions are built into those systems.

Cost
PowerISO is offered for $29.95 on the PowerISO website. This price includes free upgrades for life should the software change, and unlocks the limitations included in the demo version of the software.

Demo Limitations
The free demo of PowerISO does not, unlike many other demos, expire after a certain period of use; rather, PowerISO's demo restricts the functionality of the program. The demo version can only open and create ISO files 300 MB or smaller. The standard CD size being around 700 MB, it's quite obvious why these restrictions could become irrational should a user attempt to make use of the demo.

Alternatives
Practically any CD burning program can take an ISO image and write it to a disk, so most computers can already burn ISO images to CD or DVD.

Other functionality built into PowerISO can be added to Windows for free. ImgBurn is a free program similar that can read, create, edit and burn ISO images to disk.