Pointrollcookies store information about a PC user�s interaction with a specific website. Standard Cookies are not inherently dangerous, but they can be misused and exploited and may allow a distinct and apparently unrelated website to access the same information. If more than one website can access a cookie that has been placed on the user�s PC, that cookie poses a security and privacy risk. Tracking cookies can allow vendors to analyze browsing behavior for marketing purposes.
Answer copied from: http://paretologic.com/resources/definitions.aspx?remove=pointroll%20cookie