The Internet has undoubtedly provided an unparalleled channel for information transmission, but at the same time it has made it much easier for lies or rumors to spread quickly and thus inflict serious harm on innocent people.

Beijing resident Guo Chunping is a case in point. She is a single parent, unemployed, and has benefited from Beijing's low-rent housing program. President Hu Jintao visited her 45-square-meter apartment, which she rents at 77 yuan ($11.7) a month, three days before the new year.

However, someone posted a photo online, saying that Guo is a civil servant and she could afford to take her daughter on luxurious tours abroad.

Now the woman in the online photo has proved not to be the woman President Hu had visited. Media inquiries have verified Guo is indeed an unemployed single parent, who receives a monthly unemployment subsidy of 600 yuan from the government. What she told President Hu Jintao about her condition is nothing but the truth.

Now the white-collar worker, who first cooked up the rumor and posted it online, has published an online apology to Guo. But this case has provided much food for thought about the necessity of guarding against the dark side of the Internet.

It is not easy for website managers to monitor all the postings online, but it is possible for them to seriously deal with those postings that may damage the reputation of a person, or cause economic losses to a particular business - there have been online rumors about oranges that contain a bug that may cause serious disease and watermelons injected with a red dye that seriously affected the sales of the fruit.

Website managers need to be particularly careful about such postings as they may be posted by business rivals with a view to destroying the image of a particular kind of product or food.

Those who use the Internet as a means to spread rumors with the intention to defame individuals or ruin the reputation of business rivals should never get away with their offences.

Victims of such postings should never give up their right to bring to court the perpetrators, who should be made to pay for the offences they have committed. Due punishment of these rumormongers would deter others and send the message to all Internet users that spreading rumors on the Internet will not be condoned.

The media also need to be careful about sensational information on the Internet. They should follow the principle that investigation must be done before repeating it. Truthfulness should never be sacrificed to timeliness.