In Australia, a viewing is held prior to the funeral. It is exactly what it implies, the viewing of the deceased in the coffin, prior to interment.
After the funeral/interment of the coffin, comes the wake. The wake can take many forms from formal and dignified to highly alcoholic and out of control. It all depends on the tradition within each individual family. So-called "Irish" wakes are loud, boozy and out of control.
My family tradition is not to have a viewing (we don't have open coffins in my family tradition). After the funeral, there is a wake at the home of the next of kin of the deceased, consisting of tea, coffee, sandwiches, cake, scones, etc. It's always very dignified and respectful.
Those who hold "Irish" wakes maintain they like to send off their loved ones with a joyous party. Unfortunately, they often become so boozy that fights sometimes ensue.