Leica’s legendary M-Lenses have got quite a reputation. Take the Leica Summilux-M 35 f/1.4 for example. It's been around since 1961, back when it was the fastest wide-angle lens out there.
And Leica's legacy goes back even further to the very first 35mm film camera more than a century ago. With a few exceptions, a modern digital Leica M11 supports both M-mount and older Leica Thread ...
The Nikon F and F2 legitimized the 35mm film format for working photographers, creating the first pro-level body supported by an extensive system of lenses and accessories.