RESCU (Real space Electronic Structure CalcUlator) is optimized to create a complete large scale DFT solution including a full set of features. More specifically, RESCU is a state of-the-art general-purpose Kohn-Sham DFT package based on advanced numerical mathematics and a parallel implementation that can predict material properties on small computer clusters. It includes common electronic structure analysis tools and implements a perturbation theory extension of DFT (DFPT) which allows computing all sorts of responses functions like polarization, phonon band structures or optical properties. Addressed applicative domains are (non-exhaustive list): >>Electronic properties of nanostructures and nanodevices >>Design, fabrication, and test of high-performance Nano sensors (NEMS) >>Advanced Materials and Nanotechnology for Post-Lithium-ion Battery >>Creation of novel functional materials / nanomaterials engineering >>Next-generation semiconductors, Solar cells, Membrane, Semiconductors, Photocatalysts, Epitaxial nanostructures >>Functional Organic and Inorganic Chemistry >>Molecular design & simulations >>Interfaces between solid/liquid compounds >>Microscopy (electronic or advanced/high resolution molecular spectroscopy) studies