Chemical Abstracts ServiceA wealth of background, descriptions, tutorials, training, news, and e-seminars on the Chemical Abstracts (CAS) databases, and the numerous subject specific databases offered by the Scientific & Technical Network (STN). For recorded e-seminars click STN under the Training tab, then click e-seminars You may be asked to enter an STN Login ID to view these e-seminars. You can enter anything in this box. A proper ID is not required.