The Big Question: Why has Wikipedia changed editorial policy, and will it improve the website?

Why are we asking this now?

Wikipedia, the online encyclopaedia launched by American entrepreneur Jimmy Wales in 2001 with the idealistic intention of being an online repository of all human knowledge, announced this week that it would have to abandon one of its founding principles. To combat a growing amount of vandalism on the website, a two-month trial is being initiated whereby entries will be edited before they go up on the site. Previously, any user was allowed to make – almost – any change to any entry: this was hailed as part of the democratising power of the internet. But a sharp increase in false information – particularly in relation to people still alive – has forced a rethink.

What exactly will the new editors do?

The new policy is referred to as "flagged revisions". It allows editors to adjudicate (mainly through reference to other news sources) on changes made to the pages of a living person. The flagged revisions will be rolled out over the next fortnight, and Wikimedia, the non-profit organisation that runs the website, will monitor users responses over the trial period.

A team of "experienced volunteer editors" will oversee amendments to such pages, Wikimedia representatives said. "We are no longer at the point where it is acceptable to throw things at the wall and see what sticks", said Michael Snow, chairman of the Wikimedia board. And Mike Peel, its UK spokesman, clarified the intention: "Anyone can continue to edit these articles, but the work of inexperienced editors with less than three days' experience will be subject to review by more experienced editors", he said. "This is our attempt to create a buffer to ensure that editors do not commit acts of vandalism."

How did the Wikipedia work before?

Wales has been feted as a brilliant business mind and social innovator for tapping into a popular impulse to add to public knowledge that few people knew existed, and even fewer publicly predicted. Wikipedia still works largely by allowing anybody to login as a user and click on an "Edit this page" tab at the top of an entry. From there it's simply a case of making changes and saving them, albeit according to a policy on "biographies of living persons". Any changes are then filed under the "Edit history" of the page, and the IP address – a numbered identity that shows where the change has been made from – is also kept on record. Pages that contain unverified information are highlighted.

In terms of sheer scale, the existence of Wikipedia has helped popularise the notion that the internet is awash with seemingly infinite information. There are limits to how reasonable this view is, of course, and certainly Wikipedia is far from infinite. But with more than three million English language articles alone, covering anything from different species of caterpillar to the cast of minor Australian television shows, and with some entries running to several thousand words, the volume of information is extraordinary. Since all of it has to be sourced, and therefore accounted for in some way, much of it is reliable. And, given it is one of the most popular websites in the world, with around 65 million users each month, its utility is difficult to underestimate. There are 10 million registered users worldwide on the English language pages, and, in all, there are around 13 million articles in 260 languages.

What errors forced the rethink?

It is ironic that the changes should be announced the same day that Ted Kennedy died, given the controversy over an article about the Senator from last year, when he was taken gravely ill at President Obama's inauguration, but survived, inaccurately reported his death. That was the most high-profile error but there have been countless others, only some of which come to public attention. Robbie Williams was briefly described as "eating hamsters for a living in and around Stoke". Vernon Kay was listed dead from a yachting accident, causing the television presenter to ring panicked relatives. David Beckham was said to keep goal for an 18th-century football team; Tony Blair, an update from February 2006 reported, kept posters of Hitler on his bedroom wall. Last September, singer Miley Cyrus was falsely described as having died in a car crash, much to the dismay of her fans, while the village of Denshaw in Greater Manchester was described as "the home to an obese population of sun-starved, sheep-hurling yokels with a brothel for a pub and a lingering tapeworm infection".

And when David Cameron admonished Gordon Brown in Prime Minister's Questions for not knowing the date of the painter Titian's death, he in fact got the date wrong himself, only for some ambitious Tory apparatchik to be exposed changing the Titian entry online in a bid to protect his leader, which in turn drew further attention to Cameron's faux pas.

Haven't they been doing that for a while?

"Flagged revisions" have already been in operation on the German version of the website for over a year. And representatives of Wikimedia have been playing down the significance of this change, claiming it is only a slight extension of a policy that is already in place, and therefore not a wholesale re-evaluation of its founding philosophy. To some extent this is true: the website did employ editors already, and demands that information be well sourced, and edit histories be comprehensible, shows a commitment to reliability from the outset. On the other hand, this week's announcement does suggest that the presumption on certain articles has changed. So numerous have the errors on the pages for living persons become that the presumption is now one of incorrect information that needs to be checked.

Ultimately, Wikipedia embodies a play-off between accuracy and accessibility. In the past, managers of the website have appeared to prize the latter ahead of the former. The latest changes don't reverse this inclination, but do suggest a willingness to compromise. This won't assuage the most trenchant critics of the website, but it may go some way to convincing them that its pioneering founders don't have a blatant disregard for history.

Won't this put people off from contributing?

Inevitably, imposing restrictions on the freedom with which contributors can edit pages will inhibit some from doing so. The new policy seems to suggest that while all editors are equal, some are more equal than others. Wikipedia executives can (and do) argue that given this new procedure applies only to a very small range of pages, there's no need to think that millions of other contributors – who take care on updating entries relating to butterfly migrations, or theories of time travel, for example – would be in any way disincentivised. Theories suggesting this may be the beginning of the end of Wikipedia therefore seem premature, and not least because the website has just received $2m (£1.24m) from a philanthropic fund set up by eBay founder Pierre Omidyar, to help expand its network of volunteers.

Will new restrictions on editing pages make Wikipedia a better resource?

Yes...

* Errors relating to the entries on people that are still alive will not get published on the page.

* By sending a signal to users about accuracy, those tempted to vandalise other pages may be put off.

* The system has been a success in Germany and any new editors could be used to check other entries too.

No...

* The vast majority of pages are not subject to the restrictions imposed on pages about living people.

* Erecting barriers to users could put off people who might otherwise have edited entries, or added new ones.

* The new measures contradict Wikipedia's founding principles, where accessibility was paramount.