Aborigines were the Australian people for 60,000 years. They lived in very diverse environments, some groups were living along the coast, others on the river banks while some inhabited the deserts in central Australia. When the Europeans arrived, they were over 250 groups speaking 600 dialects.

Map of the linguistic groups by Norman Tindale

Geographic map

Some groups never used throwing sticks, others never saw a boomerang because of different hunting methods. The below examples of usage and manufacture do not portray the traditional diversity of the Aborigines but just a few stories that reached us.
The large number of words used for the boomerang and the hunting stick depending on the region and group of Aborigines show this incredible diversity.
 
Aborigines and other civilizations using the flat and curved wooden object that we vulgarly call "boomerang" today was used quite differently:
- They used it as a all-in-one tool for survival:
Hunting, fishing, gathering, starting a fire and... war.
- They used it for ceremonial dances and rituals.
- They also used it as entertainment and competition during inter-tribal encounters.
 
 
 
But how did the Aborigines made the throwing sticks and boomerangs?
 
There are in fact 2 types of curved wooden objects that are often mistakenly lumped together as boomerangs:
 
THE HUNTING STICK (aka killing stick)
 
It's a wooden stick of good size, usually over 50cm (20 inches), slightly curved, large and heavy; obviously not meant to return, even though it can glide straight and reach up to 200m (650 feet).
Unlike a returning boomerang, it is thrown horizontally and much like a skipping stone on the water surface it can bounce off the ground to reach and break the preys legs, slowing or stopping it. This one will then be killed with sticks or spears by the hunters.
 
Here are two examples:

These hunting sticks were more like weapons or tools from the Prehistoric period.
The bulk of these so-called "boomerangs" made by the Aborigines were actually hunting sticks, not boomerangs, hence the confusion by Europeans who long thought that the boomerang was used for hunting and could return once the target was hit, which, of course, is completely impossible.

THE BOOMERANG
 
A lot more curved, lighter and often smaller than the hunting stick, thrown vertically or tilted, it returns relatively well towards the thrower.
The boomerang probably evolved from the hunting stick:
Could it be that children playing with lighter hunting sticks noticed its particular returning property?
Even if the boomerang was really used for hunting, its curved flight makes accuracy difficult and limits its hunting purpose, especially for birds hunting.
This particular type of throwing stick, the boomerang, was more likely used for games and competitions.
 
Here are two examples (both at the top):

The bottom object, due to its light curve and the pointed tips of its wings, is rather a hunting stick or throwing stick (common terminology).  
Often mislabeled as the "non-returning boomerang" to categorize the hunting stick and the "returning boomerang" for the boomerang, which is redundant since boomerang means a returning throwing stick.

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