This page is a supplement to the book Mastering Shear Sharpening which can be purchased as a pdf downlead.
Chapter 4 introduces you to the parts of the shears and the correct names.
Look and Learn
Additional Information
This YouTube Playlist has dozens of types of unusual screws a sharpener might encounter. https://www.youtube.com/playlist?list=PL_Fq7SYBzMT4EpQ-Tdhy9F354Zo7MK6av