Plasma wakefield acceleration is a rapidly developing field which appears to be a auspicious candidate technology for accelerators to reduce the size of particle accelerators providing acceleration gradients a factor 10 to 1000 larger than in conventional radio-frequency metallic cavities. The Advanced Wakefield Experiment AWAKE at CERN is a high profile accelerator R&D experiment, which accelerates electrons in the wakefield driven by a proton bunch and takes advantage of the large energy stored in the proton bunch to reach high energies in a single plasma source. This presentation introduces the plasma wakefield acceleration physics and technology, shows the technological challenges, gives an overview of the state of the art and shows the results and plans of the AWAKE experiment at CERN.