ITU-R Recommendations constitute a set of international technical standards developed by the Radiocomunication Sector of ITU on topics such as efficient management and use of the spectrum/orbit resource, radio systems characteristics and performance, spectrum monitoring and emergency radiocommunications for public protection and disaster relief. ITU-R Reports contain technical, operational or procedural statements prepared by radiocommunication study groups. ITU-R Handbooks provide a statement of the current knowledge, the present position of studies, or of good operating or technical practice, in certain aspects of radiocommunications.