Film Camera Bodies

Nikon S Series

Rangefinder cameras using 35mm film. Their appearance and operation are Contax-style.
They use the S mount.

Nikon F Series

A series of SLR cameras using the F mount from Nippon Kogaku (now Nikon).
This series has continued from the release of the "Nikon F" in 1959 (Showa 34) to the present day, and is sometimes referred to as the "unchanging F mount."

F Single-Digit Series

A series of professional flagship models.
From the Nikon F4 onwards, they became autofocus.

NIKKOREX Series

A series of entry-level (mid-range) cameras. Manufacturing was outsourced.

Nikomat Series

A series of inexpensive Nikon F-mount SLR cameras developed after the failure of the Nikorex series, which attempted OEM supply. Development and manufacturing were handled by Nikon to maintain Nikon's quality standards while reducing costs.
The lineup included the Nikomat FT series with mechanical shutters and the Nikomat EL series with electronic shutters and aperture-priority AE.

Nikon FM Series

A series that succeeded the Nikomat FT series with mechanical shutters.

Nikon FE Series

A series that succeeded the Nikomat EL series with electronic shutters and aperture-priority AE.
It is a sister series to the FM series.
Both series were integrated with the release of the Nikon FM3A in 2001.

Nikon EM Series

A series of entry-level models positioned below the FM/FE series.
The successor to the EM was renamed the FG.

F Two-Digit Series

A series of autofocus SLR cameras compatible with D-type lenses.
The F100 (though a three-digit model, it's included in the two-digit series) was also known as the "F5 Junior," condensing the high performance of the large and heavy F5 into a compact body.
It featured a magnesium alloy body and high rigidity, making it a model robust enough for professional use. It was produced from 1998 to 2006.

F Three-Digit Series (F-)

A series of mid-range to entry-level models. While primarily autofocus, it included two manual focus cameras: the F-301 and F-601M.
The F-801 had high basic performance and was often used as a sub-camera by professionals. It was the first model introduced after the company name changed to Nikon.

Nikonos Series

All-weather cameras. Not just water-resistant for daily use, but a series of system cameras capable of underwater photography.

Photomic

A viewfinder with a built-in exposure meter.

"Gacha-gacha"

Refers to the act of physically communicating the lens's maximum aperture value to the camera body.
The camera has a lever, which engages with the "crab claw" at the base of older lenses.
The aperture is turned to its minimum value and then back to its maximum. This action produces a "gacha-gacha" sound.
This operation is necessary to couple the exposure meter.

Lenses

Nikkor

The brand name given to Nikon lenses.

Nikkor Auto

The oldest group of F-mount lenses. Also known as non-AI.
They were the first in the world to establish an automatic aperture-meter coupling system that linked the lens aperture to the exposure meter.
Lenses later modified to the AI system are called Ai-converted (Ai-kai).

Ai

Abbreviation for Automatic Maximum Aperture Indexing.
A system that automatically transmits the maximum aperture value to the camera body. Compatible camera bodies have a coupling lever that engages with the exposure meter coupling guide on the base of an AI lens, allowing the aperture's maximum value to be transmitted. The "crab claws" have holes, making them distinguishable.
Nikon officially offered a service to convert early lenses to AI.

Ai Nikkor

A group of F-mount lenses compatible with Ai.
Bright lenses with a maximum aperture of F5.6 or wider have "claws," allowing for the older coupling method as well.

Ai-S

Lenses improved so that the amount of movement of the aperture-stop-down lever is proportional to the actual amount of aperture stop-down.
There is no difference in lens rendering between "S" and non-"S" versions.

PC Nikkor

Lenses capable of shift and tilt movements.

Ai AF

Lenses released during the era of autofocus film cameras.
They use the AF motor inside the camera body to operate autofocus.
While they can be used with digital SLR cameras, AF will not function on models without a built-in AF motor.