Pecha Kucha are presentations that follows a couple of simple rules.
First, the presentation contains twenty slides.
Second each slide plays for twenty seconds, then automatically switches to the next slide. The presenter does not exert any control over slides advancing.
So in six minutes and forty seconds the presenter has completed their time with the audience.
By way of simple explanation, let's look at a sample Pecha Kucha, which will recap these rules as well.