The conundrum, for the strollers was, can I go and
cross every bridge, once and only once?
And cover all these sections of the city.
Is there a way to do this?
And nobody knew how to do it.
And indeed by converting it into an abstract problem,
Euler was able to show that no such path existed.
That later, a path like that was later called an Euler path in his honor,
That's the origins, a good story, those are the origins of graph theory.
And graph theory was a mathematical concept useful for
many years, used by mathematicians, but
not that important to real world applications Until the 20th century.
The 20th century coupled with computers, many computational problems,
including optimization problems, including deduction problems,
including matching problems, including looking things up and databases,
all could be seen at, you could get incredible insights in these problems
by representing these things as graph theory prompts.