Characterized its collection of snippets, taken off of

Google. Inc has been vaccuming up fragments of people's online activities broadcast over public Wi-Fi networks for the past four years, a breach of Web etiquette likely to raise more privacy worries about the Internet search leader.
Even Google was troubled by its behavior, and issued a public apology Friday. The company said it only recently discovered the problem in response to an enquiry from German regulators.
"Maintaining people's trust is crucial to everything we do, and in this case we fell short," Alan Eustace, Google's top engineering executive, wrote in a blog post
"Maintaining people's trust is crucial to everything we do, and in this case we fell short,"Alan Eustace, Google's Top engineering executive, wrote in a blog post.
Google characterized its collection of snippets from e-mails and Web surfing done on public Wi-Fi networks as a mistake, and said it has taken steps to avoid a recurrence. About 600 gigabytes of data was taken off of the Wi-Fi networks in more than 30 countries, including the U.S. Google plans to delete it all soon as it gains clearance from government authorities.
None of the information has appeared in Google's search engine or other services, according to Eustace.

Please explain to me the emboldened parts.
I guess "taken off of" means "taken from" though. About "characterized" I know in general it means "display a character/feature of something/someone" but I wonder what it means. Similarly, snippets generally means "a piece of news" but have no idea what it means here.

Source : http://www.ndtv.com/news/world/google-grabs-personal-info-off-of-wi-fi-networks-25706.php?u=1107