1.   These programs can scan your computer for viruses every time you start up or even continuously.

2.   Anti-virus programs can quickly scan anything that comes into your computer looking for the unique signature characteristics of known viruses.

3.   For systems using voice, a speech-recognition program would scan for voices full of stress or annoyance.

4.   Once up and running, the programs scan your hard drive for relevant files, compress and encrypt them, dial your Internet connection and perform the initial backup.

5.   The iClean program will scan the Mac, inform the user of how much space can be saved and will even empty the Trash if so instructed.

6.   These programs scan Internet content for pornography, hate speech, violence or other material deemed inappropriate.

7.   These programs automatically scan your hard disk and look for viruses.

8.   This amazing little program quickly scans the hardware and software on your computer and produces a Web page of detailed results.