"SECURITY - Not a dirty word, Blackadder." The issue with regard social networking is the personal security aspect (individual privacy), or operational security (Classified Operational detail). Those joining the Armed Forces need to be discrete & keep their personal details such as their name, address & contact details deliberately unrecognisable. FaceBook has supposedly begun to address this issue following complaints with regard the complexity of excluding access to your data - as obviously this is how they generate revenue, they are loathe to restrict access to your personal information because it is commercially useful. It is also very useful to the ill-disposed. For the dissemination of potentially sensitive information, personal email is by far the preferred route between a unit and the individuals within it, but even then people forward details to mates without thinking about the "need to know" implications and pass on information to people who do not need to know specifics. For generic chit-chat, you're welcome to use this site of course, but we are forever having to delete dates, times, people's actual names, mobile phone numbers, email addresses and details about exercises that the wider public should not be privvy to. MSN, Xbox & the like are probably on a par with FB, MySpace, Twitter, YouTube etc., when it comes to unguarded chatter about sensitive issues and Cheltenham GCHQ certainly has it's work cut out monitoring individuals who have no concept of how easily they can be identified or the significance of being employed in an occupation which anonymity is best employed for operational reasons. There was a plot foiled by GCHQ not that long ago which involved the kidnapping of a UK soldier from a particular ethnic group - the idea was to behead him on television "as a warning to others". Their target was selected, very simply from a social network which helped locate & identify him. These people really are out there. Spin forward a few years and the horrific Lee Rigby murder brought this into sharp focus, it was predicted more than a decade ago. The advice is to just be sensible guys. Those already serving or about to serve in an Operational Military unit should try to keep themselves low-key when discussing current military operations, exercises and training and avoid linking themselves or others with identifiable ongoing operations. If your username identifies you, we're happy to change it if you wish, just pm the new username.