Chainwire (also 'chainlink' or 'cyclone' fence) is the cheapest steel fence in the trade. A diamond mesh of interwoven steel wires hangs from steel posts, kept taut by a top and bottom tension wire. Standard mesh is 50 mm diamond, 2.5 mm wire, galvanised. PVC-coated chainwire (commonly green or black) shows up in sports fields and tennis courts.
Chainwire goes up fast and offers transparent boundaries (you can see through it), which suits sports fields, builder's hoardings, animal yards, and rough perimeters. It's not a security fence on its own (bolt cutters defeat any 2.5 mm wire) but with anti-climb mesh density and barbed-wire toppers it serves as a deterrent.
Not a residential look. Chainwire shows up in suburban Australia mostly on industrial estates and rural properties, rarely on a home boundary.