https://www.tempertemper.net/blog/using-horizontal-rules-in-html
Using horizontal rules in HTML – tempertemper
The horizontal rule is pretty widely misunderstood and often abused. It’s not an HTML element I reach for very much, but it’s worth writing about.
horizontal rulesusinghtml
https://webkit.org/blog/14933/bringing-back-horizontal-rules-in-select-elements/
Bringing Back Horizontal Rules in Select Elements | WebKit
horizontal rulesselect elementsbringingbackwebkit
https://www.sarasoueidan.com/blog/horizontal-rules/
Not Your Typical Horizontal Rules
– The personal website of Sara Soueidan, inclusive Web UI engineer
not your typicalhorizontal rules
https://developer.chrome.com/blog/hr-in-select
Select element: now with horizontal rules | Blog | Chrome for Developers
Learn how expanded select element capabilities enable visual horizontal breaks for better grouping.
chrome for developersnow withhorizontal rulesselectelement
https://iteducationcourse.com/horizontal-asymptotes/
Horizontal Asymptotes: Definition, Rules, Equation and more
Oct 28, 2022 - Horizontal asymptotes occur for functions with polynomial numerators and denominators. These are known as rational expressions.
and morehorizontalasymptotesdefinitionrules