What do the different umbrellas mean?

The umbrellas represent various pre-defined network protection levels provided by Island. A higher number of umbrellas indicate an increasing level of protection. A single umbrella represents protection against the most serious types of Internet threats, such as malware and phishing sites, that pose a direct threat to your systems. Additional umbrellas add protection against Internet sites which may contain material considered objectionable or undesirable to the end user.