pulses can be less than 100 femtoseconds. Instruments There are six experiments conducted inside the XFEL by the scientists from all over the world. All of these experiments use the X-rays. Femtosecond X-ray Experiments (FXE) Single Particles, Clusters, and Biomolecules & Serial Femtosecond Crystallography (SPB/SFX) Spectroscopy and Coherent Scattering (SCS) Small Quantum Systems (SQS) The SQS instrument is developed to investigate fundamental processes of light-matter interaction in the soft X-ray wavelength radiation. Typical objects of investigation are in the range form isolated atoms to large bio-molecules, and typical methods are variety of spectroscopic techniques. The SQS instrument provides three experimental stations: Atomic-like Quantum Systems (AQS) for atoms and small molecules Nano-size Quantum Systems (NQS) for clusters and nano-particles Reaction Microscope (SQS-REMI) enabling the complete characterization of the ionization and fragmentation process by analyzing all products created in the interaction of the target with the FEL pulses Photon energy range between 260 eV and 3000 ev (4.8 nm to 0.4 nm). The ultrashort FEL pulses of less than 50 fs duration in combination with a synchronized optical laser allow for capturing ultrafast nuclear dynamics with unprecedented resolution. High energy density matter (HED) Materials imaging and Dynamics (MID) The scope of the MID instrument are material science experiments using the unprecedented coherent properties of the X-ray laser beams of the European XFEL. The scientific applications reach from condensed matter physics, studying for example glass formation and magnetism, to soft and biological material, such as colloids, cells and viruses. Imaging Imaging covers a broad range of techniques and scientific fields, from classical phase-contrast X-ray imaging to coherent X-ray diffraction imaging (CXDI) and with applications, e.g. in strain imaging inside nanostructured materials to bio-imaging of whole cells. In many cases the aim is to obtain a 3D representation of the investigated structure. By phase retrieval methods it is possible to pass from the measured diffraction patterns in reciprocal space to a real space visualization of the scattering object. Dynamics Complex nanoscale dynamics is an ubiquitous phenomenon of fundamental interest at the forefront of condensed matter science, and comprises a multitude of processes from visco-elastic flow or dissipation in liquids and glasses to polymer dynamics, protein folding, crystalline phase transitions, ultrafast spin transitions, domain wall dynamics, magnetic domain switching and many more. The extremely brilliant and highly coherent X-ray beams will open up unseen possibilities to study dynamics in disordered systems down to atomic length