A module, at the most basic level, is a collection of functions and structures.
Modules who have the name
*/main (no matter what comes before it, so
addint/main as well as just
main both qualify) are main modules. This means they can be executed if you add a
main function to them.
If you’re familiar with other programming languages, it’s like having a
main module in golang or (roughly) a
.cpp file with a
main method in C++ (or
.c in C).
Libraries are disbributed in the foramt of a
<library-name>.chimod file, including the standard library. The standard library (which is in active development), is under the
std/ directory in the src tree of your workspace.