"We resolved the issue quickly, and we are now back to 100 percent. We're sorry for any inconvenience this may have caused," the representative said.

A company representative told CNBC that Facebook had "experienced an issue" that briefly prevented people from posting to the site.

Just after 9 a.m. London time, the site forwarded to an error message telling users the unspecified problem would be fixed as soon as possible. After 30 minutes, normal service had been resumed with the website once again allowing users to log in. Reports from news wires indicated that users from all over the world had been hit by the outage.

Facebook was briefly unavailable on Thursday morning in several countries in Europe and the United States, with the outage affecting desktop and mobile sites.

During the blackout, disgruntled users took to rival social media site Twitter to vent their frustration as well poke fun at the website, which for many people has been a part of their everyday lives since its formal launch in 2006. The "Facebookisdown" hashtag on Twitter received 49,000 mentions in the 30 minute period, according to analytics by Topsy, with 1,633 mentions per minute.



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Social news and entertainment website Buzzfeed tweeted images and videos of cat pictures during the outage to help people who were suffering from boredom.

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Online media platform 9GAG joked on Twitter that the problems could have been due to founder Mark Zuckerberg changing all his privacy settings to private. Meanwhile, many users quipped that productivity in offices around the globe could have spiked without the lure of the social network giant.

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This is not the first time that Facebook has experienced these interruptions. Brief outages have occurred in recent years, alongside similar problems at Twitter, but the most notable was in 2010. Facebook states on its website that this was—at the time—the "worst outage we've had in over four years." It lasted for 2½ hours and was caused by an "unfortunate handling of an error condition."

"An automated system for verifying configuration values ended up causing much more damage than it fixed," Facebook said at the time. A change to this system wreaked havoc for the inner workings of the site, and Facebook said it had to stop all traffic during this period, which meant turning off the site.

"Once the databases had recovered and the root cause had been fixed, we slowly allowed more people back onto the site," it said.

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Matt Navarra, a social media director from technology website thenextweb.com, told CNBC via email that Thursday's outage could be a concern for Facebook but is unlikely to worry the brands that advertise on the site.



"All services are subject to down-time here and there. A one-off outage isn't likely to dent Facebook's reputation, ... but repeat incidents could change things," he said.



"With more than 1 billion active users on its service each month, Facebook's global reach is unparalleled. Some advertisers are shifting their emphasis and digital marketing budgets away from the site due to difficulties with organic growth, but in general there is still every reason to be on Facebook."

—By CNBC.