Basically PechaKucha is a presentation style in which 20 slides are shown for 20 seconds each on a screen - which means only six minutes and 40 seconds in total for each presentation. The slides are changed automatically (configure it in your presentation program). This fast change leads to a better connection of visual audible content and encourages presentors to use visual content in a more creative way.
More interesting and precise presentation of ideas, concepts, projects...
Preparation: All presentors use a MS "PowerPoint" or a Open Source "Impress" template with automatical slide changes after 20 seconds. The moderator saves them on a computer.
Conduct: After the last slide is fading out, the presentation will be interrupted and the next presentation starts.
A winner presentation might be elected by the audience.
In the internet you will find a lot of inspiring examples how different and creative Pecha Kucha can be used. There are PechaKucha nights in some cities, you could join one and experience the method.
If Impress or PowerPoint do not work - as well PDFs may be presented.