Games can have multiple worlds, although typically only one is necessary. These worlds are isolated from each other, meaning they donot share the same entities nor component IDs.
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# Entity
An unique id.
Entities consist out of a number unique to the entity in the lower 32 bits, and a counter used to track entity liveliness in the upper 32 bits. When an id is recycled, its generation count is increased. This causes recycled ids to be very large (>4 billion), which is normal.
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# QueryIter
A result from the `World:query` function.
Queries are used to iterate over entities that match against the set collection of components.
Calling it in a loop will allow iteration over the results.
```lua
for id, enemy, charge, model in world:query(Enemy, Charge, Model) do
