The International Olympic Committee is for the first time permitting athletes to write blogs.
The IOC has set out guidelines for blogging at the Beijing Games to ensure copyright agreements are not infringed.
They include bans on posting any audio or visual material of action from the games themselves.
The move follows the increasing use of unofficial blogs by athletes in previous Games, including Athens in 2004 and the Turin Winter Games.
"It is required that, when accredited persons at the games post any Olympic content, it be confined solely to their own personal Olympic-related experience," said an IOC statement.
'Personal expression'
Posting confidential information about other people is also outlawed.
"The IOC considers blogging... as a legitimate form of personal expression and not a form of journalism," the Olympic authority said.
"Blogs should be dignified and in good taste."
The IOC guidelines follow concern that the games could become highly politicised, with China's human rights record, its treatment of dissidents and links with Sudan becoming major issues.
Some national Olympic committees in Europe found themselves at the centre of a row after being accused of trying to prevent athletes from speaking out on issues such as Darfur.
Beijing athletes allowed to blog
