The role of data in the social sciences before and since the Internet

Questions for discussion

What is called 'data'? Does it mark a certain approach in the social and political sciences?

Does the Internet modify our way to deal with data and with social and political investigation at large?

Is it worth researching the Internet? Is it doable? What does it change, in comparaison with the investigation of "real" social phenomena? What could be the specific challenges involved in online research?