Do not share your pics in chat rooms as they can be misused. Identity theft is a grave issue and can have dangerous repercussions. Always be sceptical and wary. If someone asks to be friends on a social networking site and the profile appears to match a work mate, check personally with that person before accepting him as he could be an imposter. Also be sceptical of any offers or prizes you might have been told you won, they might actually be phishing attacks.