##Week 2: Introduction to Ruby ###Intro to the Back End Required

What is the difference between front- and back-end development? Why do you need to install Ruby but not HTML/CSS?

Read the intro to back end on the Odin Project description, and the What is: Back-end web development blog post.

Sign Up for Cloud9 and create a basic Rails project.

• Go to http://c9.io
• click the GitHub icon at the right end of the page header (looks like a cat with a tentacle)
• click “Authorize Application” and confirm with your GitHub password
• On the c9 dashboard, click “Create New Workspace” > “Create a new workspace”
• In the “Create a New Workspace” dialogue:
  • give it a name
  • set privacy to “Open and Discoverable”
  • set hosting to “Hosted”
  • click “Ruby on Rails”
  • click “Create”
• The new workspace appears on the left side of the screen under “My Projects”.
• After it finishes processing, select it from the left menu.
• Click “Start Editing”, wait for a while while it initializes in a new tab
• From here, you can explore the c9 IDE. Take a look at the different presets from the “Welcome” tab, but for right now use the “Full IDE” preset
• Here’s a rundown of what’s on the screen (just the three major sections):
  • On the left you have a file browser. These directories (“app”, “bin”, “config”, “db”, etc) are the standard skeleton of a Ruby on Rails project. Normally these are generated when you create a new rails project using the rails new command, but c9 has taken care of that for you. Clicking any file will open it in …
  • The editor panel, top-right section. This section holds the “Welcome” interface, but it will also become a simple text editor when you click a filename on the left. Below that is the command line. Basically each tab here is a terminal that’s running on your virtual machine. New processes that are booted in your environment will create a new tab here, and you can see the log output. You can also use this to enter commands for your app like “rails generate model user” or “rake db:migrate” (those commands will become familiar later in the course).
  • Explore by clicking on stuff to see what it does. You’re not going to break anything, and even if you do you can just scrap the project and start a new one

Type $ ruby -v and $ rails -v into your command line (remember, the $ just represents the command prompt). You should get back versions similar to 2.0.0 and 4.0.0 (1.9.3 and 3.2.x should be okay to work with, but your Rails version will matter when we cover Rails more in depth). If you didn't get those values, you'll need to go back to the Installations Unit and get everything installed properly.

You should also be able to use $ which git and see the directory where you installed Git.

###Intro to Ruby ####Required

What is an "interpreted" language?
What is IRB?
What are Objects?
What are Methods?
What are Classes?
What are Blocks?
What is an Array?
What is an Iterator?
What are hashes?
What is a library?
What is a gem?

Do the challenges at http://tryruby.org/levels/1/challenges/0.

• Go to that URL
• In the interactive prompt, type “help” to launch the tutorial
• Keep following the instructions until it’s completed

Do the RubyMonk “Ruby Primer” course: http://rubymonk.com/learning/books/1

###Weekly Project You need to complete all the problems on the RubyMonk (starting with this one) and upload them to your deliverables Github Repo in the RubyMonk folder. If you get stuck, refer to the GitHub information in the Odin project’s walkthrough.

You should be able to run $ ruby ./rubmonkychalllengename.rb for each file and get them to work. Verify every solution is correct by using git to clone the repo to your c9 machine and then requiring each file in an irb session on c9.

• $ irb
• $ require './my_file.rb
• ...use the class or method here

“Correct” in this case means that the code executes and produces the output you expected. Don't worry about doing this for the files that only assign a variable (variables aren't exported from files when you require them).

If it does not work, don’t despair! Code that has “bugs” (a “bug” is when your code doesn’t do what you thought it would do, and you’re not sure why) is absolutely normal and debugging (figuring out what is wrong, and then fixing it - two steps) is a huge part of what developers do. Debugging is a skill like any other and figuring out why it didn’t work and fixing it is definitely time well-spent. When you are debugging code that doesn’t work, and you have no idea what’s wrong, just remember that you are not wasting time; you are working.

####Optional & Resources

• Read and complete the [Ruby in 100 minutes guide] (http://tutorials.jumpstartlab.com/projects/ruby\_in\_100_minutes.html)
• Ruby beginners guide
• Do the first Ruby exercise (Bob) on Exercism.io and respond to any feedback you receieve. Provide a link to your submission on Exercism.