Electron synchrotrons are sources of light

This document gathers short articles that describe the general features of synchrotron light sources. The first 3 documents deal with the historical aspect and development of synchrotron light sources and present the scientific perspectives of the 2 advanced synchrotron sources set on French soil: the ESRF (European Synchrotron Radiation Facility) in Grenoble and Soleil in Saclay. The following article gives a detailed and comparative account of the storing rings of ESRF and Soleil. The last article deals with the instrumentation that has been developed to respond to the more and more specific X-rays produced by synchrotrons, such as optics for spectral and spatial filtering, X-ray detection systems and the surroundings of the samples. (A.C.)