The aim of the textbook "Information Transmission" is to provide a fundamental understanding of the principles and procedures used in communication systems today. In addition to the necessary basics, the first chapters focus on digital transmission over additive Gaussian channels, and subsequently on the modeling of time-variant transmission channels, which play an important role in today's mobile communications. Optimal and suboptimal receivers with equalization methods such as Viterbi-MLSE and DFE are examined. Another important part of the book is the information theory, which is essential for overall understanding and for grasping theoretical limits, along with the introductory topics of source and channel coding, whose methods are utilized in all modern communication systems. Other topics include multiplexing and multiple access.