Big data is the phrase used to describe a large amount of data – either structured or unstructured. Ninety percent of the data in the world today has been created in the last two years alone. And most of the data is unstructured. Every minute YouTube users watch 4.1 million videos. Google delivers results for 3.6 million searches. Wikipedia users publish 600 new edits. According to computer giant IBM, 2.5 exabytes – that’s 2.5 billion gigabytes (GB) – of data was generated every day in 2012. That’s big by anyone’s standards. “About 75% of data is unstructured, coming from sources such as text, voice and video,” says Mr. Miles.