When I first started writing about the Mac, networking involved multiple protocols, cables, hubs, routers, switches and crossed fingers as you attempted to configure the whole thing in the operating system.
Wi-Fi has done away with the cables and while there are still several protocols, if you want to connect Macs and Windows machines on a network, the only two you need to worry about are AFP and SMB. Now, when you connect your Mac to a Wi-Fi network on which there are other Macs and PCs, by default you’ll see them pop up in the Finder’s sidebar.
There’s still a great deal you can do, however, to configure settings and make sure everything runs as you want it to and, importantly, you only share files and folders you want…