The safety case and trust case concepts are presented, several development methodologies are discussed. The structures of the three most common notations for representing safety cases are reviewed, with their main elements being thoroughly described and the notation argument models schematically illustrated and analyzed. Different safety systems are compared in terms of the development approaches, presentation techniques and information sources used for safety cases implementation. The general scope, goals and main principles of ForSyDE Modelling Framework are introduced. Key words: Safety case, trust case, notations, Toulmin, ASCAD, GSN, ForSyDE.
