Unknown action, No action responded to world

<http://localhost:3000/hello/world> gives:

"Unknown action

No action responded to world"

I'm following along with <http://wiki.rubyonrails.org/rails/pages/

and what stands out are statements like:

"Now take a look at app/controllers/hello_controller.rb."

Which doesn't exist for me, I had to create multiple directories. I
would've thought that a directory like "controllers" would be pre-
existing?

Anyhow, I was getting:

"Hello#index

Find me in app/views/hello/index.rhtml"

from both <http://localhost:3000/hello> and <http://localhost:3000/hello/

, but seem to have lost the thread of the tutorial.

I know that my .rhtml file should be using the variable which is defined
elsewhere, but it's not clear from this tutorial how to do that
(entirely). It doesn't specify what each file should look like in its
entirety, and I, for instance, can't follow the instruction to "Notice
the index function," because there's no such function in the file which I
created. Should I create such a function? No doubt, but the discrepancy
indicates that perhaps my configuration is mucked up. The index function
should've been created by...?

In any event, here's my decidedly primitive script which I'm using to run
my ruby stuff, and it's output:

[thufir@localhost dummy]$
[thufir@localhost dummy]$
[thufir@localhost dummy]$ pwd
/home/thufir/dummy
[thufir@localhost dummy]$ ll
total 140
drwxrwxr-x 6 thufir thufir 4096 May 13 04:15 app
drwxrwxr-x 2 thufir thufir 4096 May 13 04:15 components
drwxrwxr-x 3 thufir thufir 4096 May 16 06:06 config
drwxrwxr-x 2 thufir thufir 4096 May 16 19:42 controllers
drwxrwxr-x 2 thufir thufir 4096 May 13 04:15 db
drwxrwxr-x 2 thufir thufir 4096 May 13 04:15 doc
drwxrwxr-x 3 thufir thufir 4096 May 13 04:15 lib
drwxrwxr-x 2 thufir thufir 4096 May 13 04:15 log
drwxrwxr-x 5 thufir thufir 4096 May 13 04:15 public
-rw-rw-r-- 1 thufir thufir 307 May 13 04:15 Rakefile
-rw-rw-r-- 1 thufir thufir 8001 May 13 04:15 README
-rwxrwxr-x 1 thufir thufir 307 May 16 19:49 run
drwxrwxr-x 4 thufir thufir 4096 May 13 04:15 script
drwxrwxr-x 7 thufir thufir 4096 May 13 04:15 test
drwxrwxr-x 6 thufir thufir 4096 May 13 04:15 tmp
drwxrwxr-x 3 thufir thufir 4096 May 13 04:15 vendor
drwxrwxr-x 3 thufir thufir 4096 May 16 19:29 views
[thufir@localhost dummy]$
[thufir@localhost dummy]$ cat run
ruby script/generate scaffold dummy ; ./script/generate controller hello
index ; cat /home/thufir/dummy/views/hello/world.rhtml ; cat /home/thufir/
dummy/config/database.yml ; cat /home/thufir/dummy/controllers/
hello_controller.rb ; cat /home/thufir/dummy/views/hello/world.rhtml ;
date ; ./script/server

[thufir@localhost dummy]$
[thufir@localhost dummy]$ ./run
      exists app/controllers/
      exists app/helpers/
      exists app/views/dummies
      exists app/views/layouts/
      exists test/functional/
  dependency model
      exists app/models/
      exists test/unit/
      exists test/fixtures/
   identical app/models/dummy.rb
   identical test/unit/dummy_test.rb
   identical test/fixtures/dummies.yml
   identical app/views/dummies/_form.rhtml
   identical app/views/dummies/list.rhtml
   identical app/views/dummies/show.rhtml
   identical app/views/dummies/new.rhtml
   identical app/views/dummies/edit.rhtml
   identical app/controllers/dummies_controller.rb
   identical test/functional/dummies_controller_test.rb
   identical app/helpers/dummies_helper.rb
   identical app/views/layouts/dummies.rhtml
   identical public/stylesheets/scaffold.css
      exists app/controllers/
      exists app/helpers/
      exists app/views/hello
      exists test/functional/
   identical app/controllers/hello_controller.rb
   identical test/functional/hello_controller_test.rb
   identical app/helpers/hello_helper.rb
   identical app/views/hello/index.rhtml
aaaaaaargh
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