LinkedIn is a social networking site for professionals,It allows you to enter each and every details of your like your schooling, college, job etc.

NewsWeek allows you to generate a career tree from your LinkedIn profile.

RahulSharma Career Tree

As much as your LinkedIn profile is fill of information as much bigger tree you will get,Here in tree branches represent the education and work experience you had and circle shows the time spent on that field, As much time spent as much bigger circle you will get.