Quora

https://theeyewearforum.com/eyewear-glasses-parts/

https://www.quora.com/What-is-a-carriage-on-a-typewriter

https://site.xavier.edu/polt/typewriters/index.html

 

 https://www.quora.com/How-do-CPU-designers-decide-to-add-new-instructions-to-an-instruction-set

 

https://www.quora.com/What-is-tristate-logic-and-what-are-its-uses-in-microprocessors/answer/Balajee-Seshadri?ch=10&share=280a7b95&srid=dpGN