Cristal Vazquez had long been curious about what her three children were up to online. So when her 12-year-old daughter left her computer without logging out of her MySpace account two years ago, Vasquez seized the opportunity to check her viewing history. Among the list of 'friends' were male names she didn't recognise, including one that was extremely flirtatious in his messages. 'I was suspicious so I messaged the guy, pretending to be my daughter, and he started trying to get me to meet him,' recalls Vazquez, a marketing manager at a retail firm. 'When he sent me his phone number, I began pushing him for a photograph.' Vazquez was in for a shock - the picture she got was of a 46-year-old man. 'I called him up and told him that if he ever contacted my daughter I would not only bring in the police, I would shame him in public.' Vazquez's experience is not exceptional. Many teenagers say that contact from strangers, receiving obscene comments on their blogs and discovering photographs of themselves posted and discussed on chat forums are part of everyday life on the Web. 'We just grow immune to it,' says 16-year-old Dorothy Lui Sze-ying. 'Most of the time if you ignore them, they go away.' But the Form Four student had an unpleasant experience in December, when one of the boys she added to her Facebook list claimed he was the debating team captain of a local school. 'He wanted to co-ordinate a debate competition with my school and I actually spoke to my school adviser about it,' she says. Then the boy's messages got sleazy, so Dorothy asked a friend to check up on him and found that the person didn't exist. 'I wondered what would have happened if I had actually met him,' says Dorothy. Not all teenagers are so fortunate. In May, the Court of First Instance heard the case of a 13-year-old boy who was sexually abused by a man he first met on the internet. Earlier that month, the police recovered the remains of a 16-year-old who had left home after getting into the sex trade through men she had met online. Hong Kong youngsters are less concerned than their parents about the risks of meeting strangers, according to an online study by software security firm Symantec. Although 93 per cent of parents surveyed between December last year and February indicated that they were concerned about having their children 'offended' by strangers online, only 13.5 per cent of youth respondents shared their concern. Nevertheless, one-third of youths surveyed said they had made friends online, with the youngest bracket, 13- to 15-year-olds, the most likely to make friends through social networking sites. The survey also found that 64 per cent of youths spend up to five hours a day online and only 5 per cent of parents know all the websites their children visit. Form Six student Ricky Cheng Ka-chun, for instance, turns on the computer as soon as he comes home from school and doesn't turn it off until bedtime. Ricky says he goes online to access the dictionary and research topics but also takes breaks to chat with his friends on MSN and browses online forums, posting comments on issues ranging from the Olympic torch to pop stars. At weekends he updates his Xanga blog and checks Facebook, where friends share photographs and play games with people around the world. Such activities help teenagers to communicate more freely, but experts say youngsters often put a lot of information on the Web that could be misused. Most Hong Kong Xanga blogs reveal photographs and instant messaging contact details or phone numbers. Enter an adult chat forum as an 18-year-old girl and you could soon attract a slew of flirtatious or obscene messages. Many teenagers think they can handle the internet and that they aren't giving too much away about themselves, but often they are, says Ken Ngai Yuen-keung, web director of the Hong Kong Federation of Youth Groups. 'It is sad to see young people on adult-content websites and forums, and to know that many choose to go there, but we need to make them aware of the consequences.' To raise students' awareness, the federation has launched a competition and a charter on good online behaviour. 'We don't know if kids actually follow all the guidelines but the first step is that they become aware of the risks,' Ngai says. Those risks can increase when young people take their online interactions into the real world. 'I know a couple who met online and are now going out, so not all the endings are bad,' Dorothy says, but concedes horror stories in the news show it's common sense not to meet with online 'friends'. The experience of Form Seven student Cheng Po-yan also suggests that teenagers may be relaxing the safety limits they set for themselves. 'A few years ago, I was firm about rejecting invitations from strangers to chat, but now that's become normal,' the 18-year-old says. Still, the recent celebrity photograph scandal involving Edison Chen Koon-hei has made Cheng more cautious about sharing photographs online. 'Even if you post photographs to share them with friends, strangers could save and edit them,' she says. 'You really do lose your privacy in the cyberworld.' Boys can be just as vulnerable. In March, 17-year-old Benny Yip Sui-yu discovered that his photographs of school friends in funny poses were being discussed on an online forum. 'I felt uncomfortable because some comments were obscene, but it's to be expected because it happens so often,' he says. Such postings can lead to cyber-bullying, which can be more serious than the playground variety because it follows the child into the home, says internet safety advocate Marian Merritt, author of the Family Online Safety Guide. (Nine in 10 local youngsters were involved in such activity last year, either as perpetrators or victims, according to a survey by the Hong Kong Playground Association.) 'It's 24/7 and removes any feeling of being safe,' Merritt says. 'It could have serious consequences especially in children already prone to depression.' Cyber-bullying led to the suicide of American teenager Megan Meier in 2006 after an online 'friend' - later revealed to have been concocted by the parent of a school friend - rejected her and posted nasty messages about her. Photos on the Web might affect teenagers' future college or job applications. 'If your grandma would be embarrassed to see it, don't put it online,' says Merritt. Teenagers are also more vulnerable to identity theft and more careless about the security of their personal documents, so the onus is on parents to update the appropriate software. Parents also need to learn about the internet, says Alain Li Chung-keung, a teacher at St Mary's Church Mok Hing Yiu College who has organised talks by experts for families. 'One expert advised parents to keep the computer in the living room so they could monitor their kids' [activity], but if your child is a teenager and is used to the computer in his bedroom, it can be difficult to break the habit,' Li says. 'We need to start educating the parents at primary-school level. Our parents may have missed the bus.' Vasquez learned that lesson when she confronted her daughter about her online activity. Not surprisingly, the teenager saw her mother's actions as an invasion of privacy and was deeply resentful. Merritt suggests that parents learn about the internet from their children. 'Kids love to teach their parents, so it's a good idea to get them to show you how to play an online game or set up a social networking website,' she says. Parents can use software to filter out inappropriate content and track their children's Web surfing, but it's best to talk to them about their habits, Ngai says. 'It would be great if parents could read their children's blogs and chat with them online,' he says. Blogs could become another mode of communication rather than a barrier, a way for children to share thoughts with their parents they would be shy of handling in a conversation. 'It shouldn't be seen as a battle, because the parents rarely win,' Ngai says.