Google has revealed that a lack of disk space is what caused its fledgling social network, Google+, to spam users with multiple notification emails for each new event.

Some Google+ users were understandably disappointed when, on seeing a plethora of new friend add notifications and assuming that their hilarious answers to the mundane profile questions had gone viral, they discovered it was in fact one new friend update sent 26 times.

Appropriately, Google's head of social, Vic Gundotra, posted his heartfelt apology on Google+.

Sorry seems to be the hardest word

He wrote, "Please accept our apologies for the spam we caused this afternoon.

"For about 80 minutes we ran out of disk space on the service that keeps track of notifications. Hence our system continued to try sending notifications. Over and over again. Yikes.

"We didn't expect to hit these high thresholds so quickly, but we should have.

"Thank you for helping us during this field trial, and once again, we are very sorry for the spam."

Twitter will add Promoted Tweets adverts into your timeline within the next month.

The addition, which has been planned for over a year, will see adverts and messages from companies and brands you already follow appear at the top of your timeline.

The "Promoted Tweets to Followers" initiative will ensure that ads are the first things users see when they log-in to Twitter.

So, for instance, if you follow Coca-Cola, communications from that company will feature at the top of your feed.

Limited interruption

Until now, Twitter users have have not been forced to put up with too much commercial interruption from the social networking site.

The current ad strategy only features the occasional promoted user/account and promoted topic on the right hand side of the page.

The Promoted Tweets to Followers ads will be much more of an intrusion, but at least the ads will be from companies and brands you already care about.

Source: AllThingsD