starkid wrote:
LANs are made up physical equipment and electromagnetic signals. I have no idea what an "abstraction" for connecting physical equipment and signals means.
That they are. Networks are made up of multiple pieces of connected equipment that send signals to each other in different "languages" or "protocols".
Modern ethernet connected hardware and software is mostly plug and play.
An everyday computer user in the 21st century doesn't need to know about OSI stuff, just plug the cables in and the hardware and software can usually figure out how to talk to each other without you having to know or do anything. In 2020 a regular user doesn't need to know how to configure network cards, figure out if crossover cables are needed or configure the network stack like we used to in the Win 95/98 days.
I guess take what you need to know from texts, but just like driving a car on turning on a TV set you don't need to know much about how it all works. I wouldn't have a clue what the compression ratio of my car is or the resolution of the TV in my lounge - I just like to use them.
If you have any problems or particular questions about networking you can pick the brains of older sods like myself. We learned hands on in the days of dial-up modems, ATM, frame relay and token ring and how to configure each connection manually. In my case we were also finishing high school and doing degrees in non IT stuff at uni. 21st century consumer level networking equipment makes all of our knowledge essentially obsolete, you just plug the RJ45 connector into the socket and the computer works the rest out for you.