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The attack on Twitter highlights the problem. For its internal documents, the company uses the business version of Google Apps, a service that Google offers to individuals free. Google Apps provides e-mail, word processing, spreadsheets and calendars over the Web.
The content is stored on Google’s servers, which can save time and money and enable employees to work together on documents at the same time. But it also means that the security is only as good as the password. A hacker who breaks into one person’s account can access information shared by friends, family members or colleagues, which is what happened at Twitter.