What are the disadvantages of using the elements that Web 2.0 covers?

• Too many people exploit the benefits of Web 2.0 without taking their time to educate people about the problems. 
  No matter how advanced the Internet becomes, it is very important for some things to be kept in a hard copy form. What happens when users begin sharing information that is copyrighted? How will people be paid for the work they do? 
• One of the key problems with Web 2.0 is dependence. If your connection should go down, how will you access the information that you come to depend on? Because many web services will be offered for free, they won't be secure, and they could easily be targeted by hackers.

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