In radiology the use of internet resources is part of the daily routine. The critical selection of but not the access to radiologically relevant information is the key topic in internet use. We offer a selection of reviewed internet sources for radiologists. We present sources that offer guidance in decision-making in daily routine as well as internet sources on technical topics in radiology. Case selection and radiological search engines are helpful sites to begin an internet research. Online anatomy sites can be of assistance for interpretation of findings in radiology. Writing and publishing scientific works in radiology requires access to numerous internet services, a positive selection of which are reviewed in the present article. A variety of freeware is available on the internet, some of which may be a substantial benefit to projects in radiology.