RegDefend is a kernel based registry protection system, designed to use as few resources as possible. Instead of polling the registry looking for changes, RegDefend intercepts the changes before they occur. RegDefend comes installed to protect registry autostarts and some special registry keys, custom rules can also be added.
The registry is a place where the operating system and applications you run store their settings and data. The registry should be protected because malicious software like viruses, trojans and worms use the registry to their advantage. The registry is the place where these programs allow themselves to be started everytime you turn your computer on. If they couldn't use the registry, the next time you rebooted they would no longer be active on your system.
RegDefend sits between the registry and applications which want to use it. If an application breaks any RegDefend rule that the user has setup then it will be blocked from doing what it wants.
Due to the way RegDefend works, it is only active when applications want to use the registry. This means there is virtually no performance loss having it protecting your system, unlike other registry protection systems which continually keep polling (reading) the registry to detect any changes. These other systems still allow malicious software to infect the registry, whereas RegDefend cannot be beaten