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starting to code

Codeville: Your program is like a network

of roads

Programs need to do different things under different circumstances. In
the game, the code displays “You win!” if the user guesses the number
correctly, and “You lose!” if not. This means that all programs, even really
simple programs, typically have multiple paths through them.

There are decision points in
every program that are like
road intersections.

The computer runs the
commands that it finds
on the “path" it takes
through the code.

There are many roads (or
paths) through the code.

A path refers to the set of instructions that the computer will actually
follow (or execute). Your code is like a street network, with lots of sections
of code connected together just like the streets in a city. When you drive
through a city, you make decisions as to which streets you drive down by
turning left or right at different intersections. It’s the same for a program.
It also needs to make decisions from time to time as to which path to take,
but for your code, it is not like driving along a road, it’s executing a particular
path.
Let’s look in more detail at how a program decides
which path to take.

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