Biggest PR fails

Social media can be a great tool for companies to spread their message and receive feedback from their customers — but there's more to it than just opening a Twitter account and hoping everything else will fall into place.

The viral nature of social networks means that information circulates rapidly and a seemingly small mistakes can quickly go around the world making the firm responsible the laughing stock of the internet.

Qantas thought it was onto a winner when it launched a Twitter competition that asked participants to describe their "dream luxury in-flight experience".

However, launching it less than a month after the airline was controversially grounded saw the plan backfire badly with customers venting their still fresh anger at the carrier.

Airlines have had their fair share of social media disasters with British Airways retweeting a racist text and Jetstar falling victims to a Facebook imposter.

But the PR blunders are a truly global phenomenon, not limited to one industry or country — here is a collection of a few of the most memorable examples from the recent past.