Washington ( CNN ) -- U.S. military personnel are officially allowed to tweet . That 's the upshot of the Pentagon 's long-awaited policy on rank and file personnel using online social media , unveiled Friday . The new rules authorize access to Facebook , Twitter , YouTube , and other social media Web sites from nonclassified government computers -- as long as such activity does n't compromise operational security or involve prohibited activities or Web sites . Until now , the military 's various branches and departments had differing policies regarding social media use . The Marine Corps , for instance , prohibited use of social media sites from its computers in 2007 , according to the Pentagon . The Pentagon announced the policy Friday via social media such as Facebook and Twitter , in addition to using the Department of Defense 's Web site , said spokesman Bryan Whitman . `` This directive recognizes the importance of balancing appropriate security measures while maximizing the capabilities afforded by 21st century Internet tools , '' said Deputy Defense Secretary William J. Lynn III , who signed the policy . The new policy denies military personnel access to sites promoting gambling , pornography or hate crimes from government computers . `` The world of Web 2.0 and the Internet provides these amazing opportunities to collaborate , '' said David M. Wennergren , deputy assistant secretary of defense for information management and technology . `` It not only promotes information sharing across organizational boundaries and with mission partners , but also enables deployed troops to maintain contact with their loved ones at home . '' The new policy allows commanders to temporarily restrict online access to maintain operations security or to address bandwidth constraints .
Facebook , Twitter , YouTube , other social media Web sites OK on nonclassified computers . Comment: New rules balance security with power of Internet , official says .