Operating Systems Mac OS, Windows, Linux, Chrome OS Command line (terminal, cmd, powershell, bash) Common Hardware Desktops, laptops, tablets, mobile devices, IoT, laser, inkjet, and 3D printers, CNC routers, digital signage, interactive displays, point of sale Network Infrastructure Ethernet cabling, OSI layers, access points, switches, gateways, DNS, DHCP, servers: file, web & mail, Active Directory, Exchange