即用CD（Live-CD）

Live-CD

If you start Puppy from CD-ROM (or from a CD-image on your harddrive) no potentially harmful programs can install on your computer. With every reboot all potential malware is gone.

However you are not wholly protected against malware while you are online, because (in theory) malware can be installed on your computer and can be active until the next reboot. That is why you should always run a firewall. Besides you can store checksums of all your files to make sure, no one has manipulated your files.