This post is by new contributor Eamonn Carey, who tweets here and is Head of Digital for MHP Communications

Why do certain things go viral and take over the world? The reality is that there’s no one answer – no one ring to rule them all. There are so many variables at play that it’s almost impossible to predict what will work and what won’t.

What Contagious tries to do is give people a primer on the constituent parts of ideas that have ended up going viral. Berger’s thesis is that ideas that have social currency, triggers, emotion, a public element, practical value and stories are the ones that become Gangnam Style successes.

Fast Company reckons Berger wants to be the next Gladwell. The book bears that out. Simply explained and illustrated with plenty of examples, this is a pop-science book for the masses rather than a exhaustive manual for specialists. Occasional repetition is irritating, but overall, it’s well worth a read.