This README would normally document whatever steps are necessary to get the application up and running.

Things you may want to cover:

• Ruby version

• System dependencies

• Configuration

• Database creation

• Database initialization

• How to run the test suite

• Services (job queues, cache servers, search engines, etc.)

• Deployment instructions

• ...

Full command Shortcut $ rails server $ rails s $ rails console $ rails c $ rails generate $ rails g $ rails test $ rails t $ bundle install $ bundle

• note that we have passed the controller name as CamelCase (so called because it resembles the humps of a Bactrian camel), which leads to the creation of a controller file written in snake case, so that a controller called StaticPages yields a file called static_pages_controller.rb.
• About page titles have a variable component, we’ll use a special Rails function called provide to set a different title on each page.
• Ruby won’t interpolate into single-quoted strings
• Everything in Ruby, including strings and even nil, is an object.
• Note the question mark at the end of the empty? method. This is a Ruby convention indicating that the return value is boolean: true or false.
• the nil object is special, in that it is the only Ruby object that is false in a boolean context
• a = [42, 8, 17] a << "foo" << "bar" (0..9).to_a a[0..2]
• (1..5).each do |number| ; 3.times { puts "Betelgeuse!" } ; (1..5).map { |i| i**2 } ; %w[A B C].map(&:downcase)
• user = { :name => "Michael Hartl", :email => "[email protected]" }
• attr_accessor :name, :email, creates “getter” and “setter” methods that allow us to retrieve (get) and assign (set) @name and @email instance variables

app/assets: assets specific to the present application lib/assets: assets for libraries written by your dev team vendor/assets: assets from third-party vendors

• Active Record comes with a host of methods for creating, saving, and finding data objects, all without having to use the structured query language (SQL)2 used by relational databases.
• Rails has a feature called migrations to allow data definitions to be written in pure Ruby, without having to learn an SQL data definition language (DDL).
• rails console --sandbox