The News of the World has become the first national UK tabloid newspaper to begin charging readers to access its online content.
Website access costs £1 for 24 hours or £1.99 for a four-week subscription.
The paper's owner, News International, has already imposed online charges for the Times and Sunday Times in response to falling advertising income.
Currently the Financial Times and the Wall Street Journal are the only other major papers to have similar paywalls.
News of the World editor Colin Myler said the paper was "an unrivalled destination" for exclusive stories - which have recently included the allegations of betting scandals in cricket.
The website aimed to make the most of that reputation, he added, giving users access to those "scoops" as well as videos and pictures.
News International also intends to launch an iPad app for the paper, with a weekly charge of £1.19.
Falling readership numbers and advertising revenues have put significant pressure on newspapers in recent years, and devising the best way to make money from content is seen as a major challenge for the industry.
Other papers, such as the Guardian, have vowed to keep content free, pinning their hopes on a recovery in advertising revenues.