Websites using some form of Captcha technology on them.
Anti-bot CAPTCHA widget that helps digitize books by providing snippets of books for people to enter the text for. Owned by Google.
ShareThis is the largest market for sharing and influence across the web, reaching more than 400 million users across nearly 1 million sites. ShareThis makes content more engaging for publishers and marketing more impactful for brands by tapping into its true influence and value. Based in Palo Alto, CA with offices in New York a...
The Platform for Privacy Preferences Project (P3P) enables Websites to express their privacy practices in a standard format that can be retrieved automatically and interpreted easily by user agents. P3P user agents will allow users to be informed of site practices (in both machine- and human-readable formats) and to automate dec...
Open graph description entity tag
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook
This page contains a meta robots tag which tells search engines and robots to index or not index the page.