Exoplanetary habitability is commonly defined as the potential of a planet to maintain liquid water on its surface - a necessary, though not sufficient, condition for life as we know it. Identifying environments that fulfill this criterion represents the essential first step - still unmet - toward the detection of potential biosignatures, which constitutes a central objective of upcoming missions such as HWO and LIFE (2040+). In this seminar, I will present a brief overview of the current understanding of terrestrial exoplanet habitability, highlighting both established knowledge and key open questions that must be addressed to inform future observational strategies of temperate terrestrial planets.