The maker's mark.
a product called Bar Keepers Friend. It's a miracle cleaner for the bottom of pans, bottom of copper pans, stainless steel sinks.
the marks have to be pointing each other in the center of the gears
The North and South Poles.
impasto
skid marks
the art is called myans art
On your top and bottom pulleys ,you have timing marks,they should line up when time is correct.
They're simply called Proofreaders' Marks.
Graduations, or graduation marks.
Date of manufacture and location
It is simply called the bottom
By the Big-Little rule, the name of an art show should be in italics. An art show is a big achievement!