Cid is the name of a character in nearly every Final Fantasy. He is not, however, the same person in every game. Just as the each respective Final Fantasy introduces an unrelated world to the previous one, a new Cid is introduced.

Although each character named Cid is different, they all follow a sort of archetype. Usually, he is a middle aged or old mechanic that has a great deal to do with the party of heroes finding, building, or repairing an airship. He is generally a helpful but minor supporting character. Usually, he isn't a playable character, but there are exceptions. The only Final Fantasy game he has been excluded from (to date) was the original; it is highly unlikely there will be another Final Fantasy without a Cid as the reuse of the name has become a beloved tradition by the fans.

  • Final Fantasy II
  • - This first Cid established the archetype character: he is an airship owner, has a bit of arrogant and harsh tone, and readily helps the group of heroes. At first, he is mercantile and unfriendly, as he charges a fee for riding his airship depending on the distance of the trip. However, once he learns the heroes are enemies of the evil empire (another reoccurring theme in the series), Cid is all to willing to help out. Unfortunately, it costs him his life. After he dies, he bequeaths his airship for the player's personal use.
  • Final Fantasy III
  • - Final Fantasy III's Cid follows the stereotypical character very well. He is an airship mechanic who is constantly helping and following the Onion Kid heroes around and tweaking their airship. Near the final battle, for some reason, five supreme spirits of good are needed. Cid, being supremely good, is one of them.
  • Final Fantasy IV
  • - Yet another mechanically inclined Cid that enjoys airship construction. This is the first Cid to join your party. Half of his 16-bit body looks like his red beard and the other half is his oversized pair of goggles. His face portrait in the menu screen gives him a young, eccentric scientist look. A loyal friend to the hero and heroine, Cecil and Rosa, Cid joins their struggle to stop the insidious Golbez. Since airship technology is incredibly powerful, as it leads to the rise of the nation of Baron and Golbez's manipulative schemes, Cid's knowledge is invaluable. He repairs and modifies the two airships Cecil and company find multiple times. In the relatively short time you can use him for battle, Cid uses a hammer to attack with and has a command that detects enemies' weaknesses.
  • Final Fantasy V
  • - This Cid is not an airship mechanic by trade. He does inevitably become one however. Originally a highly respected scholar, this Cid and his nephew Mid help Butz and the gang with solving mysteries of technologically advanced (but still ancient) ruins. Because an airship is found in one of these ruins, Cid picks of the engineering trade and lends a hand like all the previous ones. He looks just like all the other scholars, but with a different color robe to tell him apart.
  • Final Fantasy VI
  • - Cid from Final Fantasy VI breaks the main tradition of the name as he has nothing to do with the party's airship in any way. He is, however, still scientifically and mechanically minded. As a research of "Magicite", the crystallized remains of magic creatures, Cid dutifully works for the evil Empire. (Yup, reoccurring theme indeed.) He has a small red mustache and wears a weird looking yellow piece of clothing that looks like a raincoat. He comes around and realizes he's on the wrong side after a chance encounter with a conflict between the heroes and the lunatic Kefka. At the midpoint of the game, there is a sort of mini game in which the player has to feed Cid fish to nurse him to health. You can actually do this incorrectly by feeding him bad fish and accidently let him die. Personally, I find it saves considerable time and gets a much more interesting scene with Celes to just kill the old bastard off.
  • Final Fantasy VII
  • - Just as Final Fantasy VII marked some big changes in the series, Cid Highwind marked some big changes in Cid-ness. For the first time ever, he is given a last name. Also, as a main character, he can be built up and used for the majority of the game. Cigarette toting, bad mouthed, and a wizard in aviation, Cid Highwind is one of the most interesting Cids as well as overall characters in FFVII. Slightly balding around the edges with gray hair, he wears a large pair of goggles on his head. The rest of his clothing looks like a blue uniform a pilot would wear. His flying record is a bit more diverse than the others Cids because he's flow in airplanes and space shuttles as well as airships. Although he's says plenty of funny things, I remember him mostly fondly for the quote, "Sit your asses down and drink some GOD DAMN TEA!"
  • Final Fantasy VIII
  • - Final Fantasy VIII's Cid has nothing to do with airships as there are none in this one. He fittingly appears to be a professor at about fifty some years old, with moppy brown hair, a pair of spectacles, and a bit of an overweight gut. Here, Cid is the founder, owner, and principle of an battle school called Garden that trains elite mercenaries called SeeD. The creation of this institute was brought about by (get this) his concern of sorceresses from the future coming back in time and conquering the world. It's a good thing too, as one of these very sorceress Cid fears is running amok in the world. Her name is Edea and she has some past connection with Cid.
  • Final Fantasy IX
  • - Regent Cid of Lindblum is a fictitious bug called an ooglop nearly the entire game. His wife Hilda catches him in an affair, turns him into a bug with magic, then speeds away with his newly constructed airship. Zidane and his party are constantly trying to return Cid to his original form so he can build them another airship. Because his brain is significantly smaller in sub-mammal form, he has trouble doing so. One of the less successful attempts of changing him back to human ends up with him turning into a frog. Like much of Final Fantasy IX compared to the series as a whole, this Cid is a much more light hearted and comical.
  • Final Fantasy X
  • - Final Fantasy X's Cid has a gruff, cowboyish attitude as the leader of the Al Bhed people and captain of the world's sole airship. He has the trademark Al Bhed swirlie green eyes, a bald head, and is covered in disconcertingly strange Al Bhed garb. He is Rikku's father and Yuna's mother's brother (or uncle as they refuse to say in the game). Cid is somewhat of a reverse racist, as he admits that he hates those that hate the Al Bhed (which is nearly everyone who isn't an Al Bhed).
  • Final Fantasy Tactics
  • - Orlandu, otherwise known as Thunder God Cid, is likely the most powerful and unbalanced character in any Final Fantasy. TG Cid looks like a wizened old sage, but he deals out more damage per turn with his sword techniques than most characters, regardless of level or job class. In the intense, convoluted political drama that is FFT, he begins on the side of Prince Goltanna and the nation Zeltennia. For some arcane politically charged reason or another, he is forced to fake his death. Afterwards, he joins up with Ramza and his army with the express purpose of laying the smackdown on zombies, dragons, over zealous knights, and deranged cultists. He has a son named Olan, who records the only accurate account of the history of the game.
  • Final Fantasy Tactics Advance
  • - Cid is the High Judgemaster in the playful, imaginary world of Ivalice. He corresponds to Mewt's father in the real world. He's got a stylish, narrow beardy face and a sardonic grin. The entire game he rides a chocobo. If you complete every single side quest quest in FFTA he'll join your party as a Judgemaster.

Note: Final Fantasy Mystic Quest for SNES as well as the Game Boy Final Fantasies: Legend 1, 2, 3 and Adventure (which more appropriately fit in the SaGa Series and Seiken Densetsu series respectively) do not have Cids. Sources: Playing these games