Although I did see some punch cards I never used them. At the time I couldn't afford a computer with punch cards and was too young and inexperienced to work for an organization that had such machines.
Reading computer magazines and books, and eagerly anticipating getting my hands on such material. Today's kids born in an online era of infinite content just can't imagine how difficult it was back them to get technical publications and information, printed or otherwise.
My favorite is chromeOS because it requires zero maintenance and I can access all my data, apps, and preferences in minutes on any compatible device by just signing into my account.
It just feels extremely natural to me, so it's difficult to pinpoint specific features I like. But two such features stand out: the parantheses-based syntax and the extreme interactivity.
I initially got a Z80-MBC2, a Z80-based SBC that runs CP/M and other operating systems, as I had developed an Intel 8080 cross assembler and wanted to run on actual hardware the code assembled with it. It was so fun I got a V20-MBC, an SBC by the same maker that features a Nec V20 (8088 + 8080) and can run CP/M-86.
Both SBCs led me down a fascinating retrocomputing rabbit hole.
Although I did see some punch cards I never used them. At the time I couldn't afford a computer with punch cards and was too young and inexperienced to work for an organization that had such machines.