The following summarizes basic academic ranks in the French higher education system. Most academic institutions being state-run, people with permanent positions are civil servants.
Several parallel career paths exist, depending on the type of institutions. The three paths correspond to teacher-researchers (called enseignants-chercheurs in French), researchers, and teachers. The three paths are more or less equivalent and it is possible to go from one path to another one when being promoted.
Several ranks exist within each path. Increases in rank (for example, the promotion from assistant professor to associate professor) entails an increase in salary and responsibility and is subject to some conditions, such as the habilitation. The permanent ranks are commonly called "Rank A" (full professors, senior scientists) and "Rank B" (assistant/associate professor, scientist). In most cases, a complete career requires at least two open recruitment procedures, as there is no individual promotion from rank B to rank A.
Temporary positions would include PhD students, postdoctoral researchers, and temporary teachers (usually called vacataires or chargé d'enseignement). There also exist some administrative ranks, held by permanent employees and often elected by their peers, such as university president or dean. Ranks in private schools and grandes écoles are often organized differently.