The Marlin 336 was introduced in 1948 as an upgrade to the Marlin 36. The
Marlin 336 improved on the earlier model 36 by using a chrome-plated round bolt
for added strength, improving the extractor design, adopting the two-piece
firing pin from Marlin's model 93, and swapping out the flat mainspring for a
coil mainspring.
The Marlin Model 336 and the Winchester Model 94 are both classic American
rifles, their histories inextricably linked with the traditions of rural
America. Owning either is owning a piece of genuine Americana. If it's that
difficult to choose between them, do what I've done, and put one of each in
your gun safe.