Estimation is the core activity in Agile process. So making it faster and more accurate is the goal of every team. If we also can make it fun – great!
No doubt it is the one of the hardest thing – define, when your product will be shipped. So, taking into consideration all uncertainty of the estimation, planning poker proved to be the simple, but powerful estimation tool for the agile team. It was first described by James Grenning in 2002 and later popularized by Mike Cohn in the book Agile Estimating and Planning.