Logs are the values measured after drilling to determine the characteristics of the formations drilled and the fluids they contain. This CD-ROM gives a clear and concise description of the operation. Video sequences filmed on a drilling site illustrate how the sondes are used. The physical principles of the measurements by the sondes most commonly used in petroleum exploration are shown in the form of animated charts. Interactive illustration of the log which is the record of the data acquired, helps users familiarize themselves with the information it contains. A general description of how the data are used completes the section on rapid data interpretation. The various phases of interpretation are described in a practical manner, using a concrete example and at the same time introducing the implied theoretical concepts. A glossary and a quiz are designed to facilitate assimilation of various concepts introduced in this multimedia publication. Elaborated with the technical support of Schlumberger and Elf, the CD-ROM is an attractive teaching tool in English and French for both students and professionals. This product is also available, at a special price, for a multi-user purpose.