Comment by throwawaymaths

Depends. Your module can have top level member fields or declarations. (By convention these modules would be capitalized) and in that case it would be instantiated as a struct (no objects in zig)

MyModule.zig

   somefield: u32,

   fn get(self: @This()) u32 {
      return this.somefield;
   }

main.zig

   const Module = @import("MyModule"); // note there are build parameters necessary to make this a module

   fn main() void {
     var x: Module = .{.somefield = 42 };

     _ = x.get() // => 42

     ...

A module is an import external to your project. Whether or not the import has top level fields or declarations, the mechanism is the same for structs, imports, and modules. For all imports (including modules) you should imagine an implicit `struct{...}` expression surrounding the code in your file.