Destiny 2 currently works off a season system where every 8 weeks a new season will launch, offering players a huge selection of new rewards to unlock along with new game modes, artifact items and other interesting lore to completely refresh the game.
As time has gone on, the seasons in Destiny 2 have gotten more elaborate and exciting with the game modes and content introduced getting a lot more interesting.
Each season comes with a season pass. This will allow players the ability to unlock an additional set of rewards for each season rank they achieve along with some other nice goodies such as instantly unlocking an exotic weapon.
You can find a list of all past, current and potentially future seasons for Destiny 2 in the list below.