Abstract :
Despite the popularity and increasing stability of freeware and open-source applications, software is making an ever heftier dent in users?? budgets. to add insult to penury, major updates and version changes often render older formats and hardware unusable. so what can be done to alleviate this computer-age old dilemma? A device is said to be backward- or downwardcompatible if it can work with input generated by an older device. if products designed for a new standard can receive, read, view or play older standards or formats, then the product is said to be backwardcompatible.