I've often seen garments advertising "fine cotton". Is this a commercially regulated or technical term or is just marketing? Similarly, I'm aware of the different qualities of cotton as far as understanding that the following are extra long staple (ELS) variants : • Sea Island cotton • Egyptian Giza cotton • American Pima cotton Questions: (1) Does ELS solely refer to that face that each individual fibre is longer than average cotton, meaning it's more durable and less likely to pill? Or does it also refer to the diameter of each fibre being smaller, finer than the average? Or are those separate things? (2) Are Pima cotton and Supima cotton the same thing? What distinguishes them? Is Supima just a Brooks Brothers branded version of Pima cotton? Is Pima cotton a commercially regulated or technical term or is there room for marketers to bullshit you about it? (3) If a garment simply says "cotton" on the tag, beyond the hand feel, how can I determine its quality? This goes out to all you textile nerds out there. Some guidance, please!