How to Upgrade Raspberry Pi OS to the Latest Version? (2022) – RaspberryTips
Debian versionCode nameRelease date
Debian 8JessieSeptember 2015
Debian 9StretchAugust 2017
Debian 10BusterJune 2019
Debian 11BullseyeNovember 2021
Debian 12BookwormNot released yet, probably in 2023 🙂