http://www.npr.org/templates/dmg/popup.php?id=12301671&type=1&date=27-Jul-2007&au=1&pid=67266211&random=2234443413&guid=0001CF37FDCB071522F91C9161626364&uaType=WM&aaType=RM,WM&upf=Win32&topicName=Arts___Culture&subtopicName=Digital_Culture&prgCode=TOTN&hubId=-1&thingId=12301670&ssid=&tableModifier=&mtype=WM

http://www.linkedin.com/static?key=what_is_linkedin&trk=ghdr_whatis

A search engine works by taking your terms and matching it will the best sites responding to it. Search engines are full profit institutions, which that is a bad thing because they are selling things around it and it isnt public.Double click is an advertising network, NOT A SEARCH ENGINE. Linked in is a professional network where you can talk to people, look for jobs, and ask questions and recieve answers.