FF I - choose a job, then upgrade it
FF III - you get better jobs as you go
FF V - jobs are more balanced - mix and match abilities
FF X-2 - no mixing and matching, but you can change them in battle
FF XI - main job+ sub job
FF XIV - just change your weapon/cross-class abilities
FF Tactics - learn abilities from various classes to unlock new ones
FF TA - same as above, but require a bit less effort and are race-exclusive
FF TA2 - as above, but more advanced classes need to be unlocked through sidequests
FF Dimensions - FF V's system, but the jobs are split between the Warriors of Light and Darkness
FF: 4 Heroes of Light - Crown system - upgrade jobs by adding gems
Bravely Default - basically the FF V system on steroids