Jobs (also known as Classes) is something related to a character (based on their appearance) or a costume of that given class. For example, a Warrior class is something given to someone that looks like that, or a Knight class is given to someone who looks like one of them and so on. The job system (a.k.a class system) is a traditional system to the Final Fantasy series and they've appeared throughout the history of the series and beyond. The six main jobs that appeared most in the games are Warrior, Knight, Thief, Black Mage, White Mage and Red Mage. These were the first six classes that were introduced in the very first Final Fantasy for the NES and that's how the whole system got started in the beginning and it continued from then on. Any game in the series will let you change a class between a character and in most games, a job can be strictly for that character without changing their class.
You can't imagine a final fantasy game without any classes in the game, and this is been done before in a few numbered games in the series. A character can look like a class even when there's no classes in the game at all, and you can still class them as any of the jobs that person looks like.
There's been so many classes throughout all the games in the series, and it will be difficult to know in total how many there've been in the games. The job system is still growing with every final fantasy installment with new jobs being introduced and whether or not that game has classes.
Back to my game. The job system in my game won't be any different than any other previous final fantasy installment that you've seen, and you can't change classes between characters.
There's actually a dfference between a Black Mage and a Black Wizard. a black mage is someone in a robe and a pointy hat and a black wizard is someone in black clothing like a dress. These classes can also be based on their gender, a black mage can be for males and a black wizard can be for females. There's no difference between them both, they do the same thing and that's damaging the enemy with magic and status ailments.
A hunter is someone that has all the monster knowledge like knowing where their weak spots are and how to kill them. But also, a hunter needs to be careful not to be killed by a monster, so a person needs to know how to defend themselves.
There's no difference between a normal Knight and a Chocobo knight, the only difference is with the chocobo knight is that a person can summon a Chocobo (like a Summoner) to join the party.
Being a Summoner is important as being a King or a Princess. A person can summon magical beasts to do massive amount of damage to the monsters, but to do that, a summoner must confront a beast to make it join the summoner. All summoners go by a name like a king or queen as majesty and highness. If that person is female, then that summoner goes by the name of Lady and if that person is male, then that summoner goes by the name of Lord. Being a summoner is not always about killing monsters and protecting the world - although that's their main priority, but summoners can also be used for stage performances - showing off their summons for display -a summoner has got to have fun as well, if that person isn't protecting the world from evil.
There's a difference between a Lancer and a Dragoon. A lancer is someone in clothing with bits of armor and a dragoon is someone that is fully armored. Lancers are less advanced than dragoons and less skillful and dragoons are more advanced and more skillful. Any male and any female can be either one of them, but a person must start off as lancer before that person becomes a dragoon.
A Conjurer is a summoner who is less advanced than actual summoners. To be a conjurer, a parent must give their child the summoning powers to become one and to be a summoner, a person must intend a summoning school. Conjurers are just as good as summoners, but with less summons and less white magic.
There's no difference between a Thief and a Bandit, they both do the same thing, but with a different name. A thief (or bandit) is someone who loves to steal things from people and this can be anybody in the world - whether that person is stealing for a purpose or for fun. This can also go into gender: a thief can be for females and bandits for males.
Blue Mages are like Hunters, but instead of knowing where the monster's weak spots are, how to kill them and defending themselves, a blue mage can learn monster's abilities. A blue mage can learn them through items, or upon use of that ability when that monster uses their ability. Not all, but only certain abilities can be learned.
A Spell Mage is a combination of a Black Mage and a White Mage with other ones in included. It's similiar to a Red Mage, but that person can equip any weapon. A spell mage will have a number of abilities from other classes, instead of just black and white magic.