This study is a linguist’s attempt to analyze such terms as human-computer interaction, computer-human interaction, human-machine cooperation, machine-human collaboration, and many related terms. The purpose of this analysis is to determine whether and how they represent different shades of meaning, some nuanced, some distinctive. This allows for their further systematization and the identification of terminological synonymy. The discussion shows that terminological choices might be necessary - not only between „man“ and „human“ or between „dialogue“ and „dialog“, but also between „cooperation“ and „collaboration“ as well as „dialog“ and „communication“. This still leaves a considerable number of terminological options which can be assigned to different facets of human-computer interaction.