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Now let's go ahead and
write our first module.

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Writing a module is very
similar to writing a class.

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Modules follow the same rules as
classes and use camel case for naming.

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When we create a module,
we use the Ruby keyword Module,

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followed by the name of the module in
CamelCase and then the keyword end.

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Let's see how that works
now using WorkSpaces.

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Okay, so let's go ahead and
see how to write a Ruby Module.

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Now I've gone ahead and
launched a new Ruby workspace.

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So go ahead and
close this welcome markdown file.

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Now over on the left side right click and
choose new file.

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We're going to name this
simple_module.rb And

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now, it will open up in
the main text editor.

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Writing a module is just like
writing a class except instead of

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using the class keyword, we use module, so

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type in the module keyword and
then the name of the module that you want.

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Now I'm going to call
this SimpleModule and

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then press enter and write the word end.

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Now let's go ahead and
see how this works inside of irb.

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Click down into the console on the bottom
of the screen and type in irb.

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Now we have to get our simple
module program loaded into irb.

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We do that by typing load,
then a space, quote and

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then the path to the simple module file.

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Which is right here so type ./ and
then the name of the file,

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which is simple_module.rb and
irb will return true.

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So now you might wonder how
we access simple module.

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Now we can't initialize it like a class.

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So normally we could say class.new, but

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we can't do that when we're
working with modules.

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Just accessing it will
return SimpleModule.

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So this doesn't do much right now, but

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what we could do if we wanted
to was store a constant in here.

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So lets say we wanted to return
the version of this SimpleModule.

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We could create a constant called
VERSION and set that equal to 1.0.

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Now constants are their own thing,
in Ruby kind of like modules,

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they're written in all upper case,
and they can't be changed.

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So once we type in this version here,
it's gonna be locked at 1.0.

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Now since we've changed this file and

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saved it,
we need to reload it into our irb session.

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So I'm going to clear the screen and
in order to do that,

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I'm going to press the up
arrow a couple of times

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until that load statement
comes back up and there we go.

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Now if we want to access
the version inside of this module,

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we do that by typing SimpleModule, and

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then two colons, and the word VERSION and
that will return 1.0.

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When we access something using with
two colons, it's called the constant

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resolution operator, and that's what we
use to access something inside of modules.

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Try creating a module on your
own now using WorkSpaces.