A once ancient art of communication, smoke signals can be handy in modern days
Knowing how to communicate using smoke signals is incredibly useful. For example, in ancient China, soldiers communicated using smoke signals to warn of incoming attacks. They could send information across the kingdom faster than the enemy could approach by signaling from tower to tower along the Great Wall. In this way, they secured their terrestrial domination.
In modern days, people use smoke signals to communicate unstructured information across two or more points that are visible to each other. Signals such as an image of a smoking cigarette, with a red strip diagonally, inform people not to use smoke signals in the area.
Additionally, this form of communication can be used by inanimate objects. Buildings are a good example. Buildings on fire use smoke signals to call on firefighters.
Next time you're on fire, consider using smoke signals.