Canon vs Nikon
Products
Generally, Canon have better lenses and Nikon have better bodies. For example, the Nikon Z-mount cameras versus the Canon EOS R and the Nikkor Z-mount lenses versus the wonderful, fast Canon RF-mount lenses.
Nikon are usually more expensive while Canon are usually less so. For example, the Nikkor F-mount 70-200mm/2.8 ($2800) versus the Canon EF-mount 70-200mm/2.8 ($2100).
Nikon are usually playing catchup with regard to lenses (with the exception being their low-end lenses which are better than Canon's low-end offerings). It seems as soon as Nikon create an answer to a Canon lens, Canon come out with a newer version that betters it. For example, the various versions of the 70-200mm lens by both companies and Nikon have yet to come out with something that competes with the Canon RF-Mount 28-70mm/2.0 lens. Like-wise, Canon seem to always be playing catchup with their camera bodies. The sole exception and where Canon have a clear advantage is with their dual-pixel autofocus system.
If just starting out in photography, go with Canon. They have the dual-pixel autofocus and are planning on adding IBIS to their new cameras. They are dedicated to making good, large-aperture lenses for them. It's all about the lenses! If already owning Nikon lenses then sticking with Nikon is a smart idea as the differences are too little to warrant changing over.
This is not important, but most of Canon's products are made in Japan. Nikon cameras and lenses are made in Thailand, China, etc.
No one ever mentions this, but Nikon cameras look much better than Canon ones. Nikon have hired italian designers in the past to help design their cameras and as such they are very aesthetically pleasing even to this day. But, this will not help photographs look better.
When it comes to the pixel race, no manufacturer is really ahead of the other. The same for ISO.
Customer Service
Canon Nikon
Revenue ¥3.557 trillion ¥887.5 billion
Employees 198,307 24,409Canon are several times the size of Nikon and as such they have much better customer service. Nikon just do not have the resources that Canon do so all their efforts go into research and development.
With the release of the EOS R5 and EOS R6, Canon have surpassed Nikon in terms of both lenses and bodies. Canon have surpassed Sony, too. Along with the great Canon glass, the R5 and R6 are such good cameras that Nikon are left floundering in this new age of mirrorless design. If buying into a new camera system and money is no object then Canon should be at the top of the list. Canon can thank their huge research and development department for this new found success.
Nikon have finally caught up with the industry in terms of camera bodies with the introduction of the Nikon Z9. They have also nearly caught up in terms of lenses.
Canon do not have anything that competes with the Nikon Z9. The yet-to-be-introduced EOS R1 will compete with it.
History
Nikon
A few optical companies (Tokyo Keiki Seisaku-sho's optical division, Iwaki GlassSeisaku-sho, and Fujii Lens Seizo-sho) combined to form Nippon Kogaku (Nikon) in 1917. Nippon Kogaku stands for Japan Optical. Nikon used to produce lenses for Canon cameras and they were primarily an optics company until the release of the Nikon F SLR system in 1959. Nikon still make F-mount lenses to this day but changes are in the works and this may not always be the case. It was a very rugged and advanced system for the time. Nikon relished in their success. They were met with another wave of success when they came out with the Nikon D series cameras in 1999.
Canon
In 1937, Canon forerunner Seiki-Kogaku Kenkyusho (PrecisionOptical Laboratory) incorporates into Seiki-Kogaku Kogyo K.K. (PrecisionOptical Industry Co., Ltd.). This is Canon Inc.'s official year of founding and they were dedicate to producing affordable Leica-copied cameras.
Canon used to have a different mount which they promised was future proof. They abandoned that mount in 1987 for an all new electronic one. Professional photographers began moving over to this system in the 1990's until Nikon introduced a practical DSLR in 1999.