Weldmesh is the term given to the kind of barrier fencing that is manufactured in square or rectangular mesh from steel wire, spot welded at each intersection.
It is usually affixed to steel uprights. Weldmesh is a relatively cheap fencing solution but has the advantage over chainlink wire of not bending so easily and not being so easily cut. It is therefore ideal where a low level of security is required but where chainlink fencing is too easily overcome.
Weldmesh is also sometimes used as rebar in reinforced concrete.