In recent years, several research and disciplinary areas have been focusing on analysing and developing theoretical concepts about genres and genre relations (Bronckart 1997; Adam 2008; Maingueneau 2014; Swales 2004; Devitt 2004; i.a.). As a result, multiple concepts related to genres have been introduced. However, these concepts are not always clearly described, distinguished or characterized. This paper intends to present and to define different proposals by several authors (Rastier 2001; Swales 2004; Devitt 2004) and to compare them with other theoretical reflections about the same issues (Adam 2011; Maingueneau 2014). This contrastive analysis shows that misconceptions may arise as a consequence of using the same label to refer to different concepts and adopting different labels to refer to the same concept. Occasionally, possible examples of conceptual overlapping were detected. These reflections are, therefore, intended as a contribution to ensure that the concepts are more clearly understood.