As others have said, they've obviously tracked the general tech improvement in CPUs, RAM, and storage. And in this way they've always danced back and forth wit

As others have said, they've obviously tracked the general tech improvement in CPUs, RAM, and storage. And in this way they've always danced back and forth with the engineering/product tradeoffs for the portable format versus a desktop system of the same period. I've always been using notebooks or ultraportables in the 12"-14" screen size class. I started with a chunky Dell Inspiron before moving to Thinkpads like the T20 and X22 and a Sony VAIO in the very late 1990s. I stuck with many generations of Thinkpads. My most recent work machine is a Thinkpad T495 from right before COVID. Qualitatively, they've given me a similar experience due to the form factor and always running some form of Linux. I preferred the 12" models when flying several times in a week but 14" when spending weeks in one place. I think this will remain true, much like smartphones have found certain form factors and just keep iterating on numerical specs while fitting the same hands and eyes. IO and expansion went from serial, parallel, and PCMCIA slots to PC Card and USB, to mixtures of USB speeds and now primarily USB-C. Other oddball IO like firewire and e-SATA came and went. Communications went from external to integrated modems, external to integrated ethernet, and external to integrated WiFi. Now, wired ethernet is starting to disappear or at least shift back to some kind of dongle. Removable storage went from floppy to CD-ROM to DVD and went away entirely. Other oddball devices came and went. Now mostly it is just networked storage services or potentially massive USB thumb drives. External display connections went from analog VGA to DVI, DisplayPort, and HDMI. Internal LCD backlights went from fluorescent to LED. Internal LCD aspect ratios went from 4:3 to 16:10 to 16:9, and now seem to be moving back to 16:10. Internal LCD resolutions went from terribly low (800x600 etc. at 14") to acceptable (1920x1080 at 14") to ridiculous (4K at 14"). Batteries went from NiMH to Lithium ion and from removable to built-in and not really user-serviceable. Some machines gained long battery run times, but often the advances seem to have been invested in reducing sizes instead. Better idle efficiency allows a machine to be on and connected for "a whole day" (by someone's definition) but actually running them at full load still depletes the battery in a small number of hours (or less).