When you write a file with some code, how does Julia know where to find it?
From the REPL
include(/path/to/file.jl) does the trick. This has the same effect as typing the code in the REPL. The same can be done inside another file.
But what if you have a big chunk of code that you want to be reusable? What if you want to use someone else's code? This is where packages come into play.
You can also load modules that are not packaged as packages by putting their directories into the
LOAD_PATH environment variable.
We will not use this approach. It is easier to package everything as a package instead.