PCCare is NOT an anti-virus product, it simply executes two tasks that are part of your existing anti-virus suite:
Updating anti-virus definitions is the mechanism that all anti-virus programs use to detect patterns in files or behavior that signify a virus infection. These patterns are used to scan all incoming files and email messages to ensure they are safe and clean.
Scanning your hard drives is the task that checks your files to make certain that any viruses have not made it past the anti-virus filters.
While all anti-virus packages provide methods for updating definitions and executing scans, PCCare acts as a "belts and suspenders" extra protection step. How many times have you aborted your anti-virus update or scan because you were busy working when the action started? PCCare gives you a second chance to update your definitions, at least once a week or as often as once a day.
If you cannot find or do not know how to use the update anti-virus definitions or scan hard drives features of your anti-virus software, you can easily use the task settings pages of PCCare to schedule these tasks for times that are convenient to you.