Document sharing tools are the online document that can exit by many people in different computers at the same time. I learn how to use this kinds of idea, and I realize it is really helpful for people to exchange their ideas and problems. The tool I preferred is “Meetingwords “( http://meetingwords.com/ ). It is free , it can help people clearly know who is adding the post, because different people have different colors, and this online software can show the time of the modifying, that avoid people stealing other people’s idea. On the country, “Meetingwords ” also have some cons. For example, the online document can only be saved for seven days from the last time you had them open, then they will be deleted by the system. I think I will use this tool in the future, maybe I will use it to help me exchange my ideas with my classmate for our project.