One of the few words that have really puzzled my English vocabulary are : nerd and geek. These terms are used differently by different people. They are what linguists call portmanteau words which you can use according your temperament or mood. However, what I learned from a long observation of how native speakers of English use them is that these words are at odds with each other and sometimes at war.
Dailyinfographic has shared with us this really cool graphic on the difference between geeks and nerds. The facts and stats featured are really amazing and I am pretty sure you will have many "aha" moments going through it. I am not sure if the picture is clear yet for me or not but I definitely learned a lot from this beautiful visualization