8 files changed, 22 insertions, 42 deletions
diff --git a/guides/source/action_view_overview.md b/guides/source/action_view_overview.md
index 09fac41491..3c1c3c7873 100644
--- a/guides/source/action_view_overview.md
+++ b/guides/source/action_view_overview.md
@@ -725,7 +725,7 @@ Returns a select tag with options for each of the seconds 0 through 59 with the
 
 ```ruby
 # Generates a select field for seconds that defaults to the seconds for the time provided
-select_second(Time.now + 16.minutes)
+select_second(Time.now + 16.seconds)
 ```
 
 #### select_time
@@ -1429,7 +1429,7 @@ This sanitize helper will HTML encode all tags and strip all attributes that are
 sanitize @article.body
 ```
 
-If either the `:attributes` or `:tags` options are passed, only the mentioned tags and attributes are allowed and nothing else.
+If either the `:attributes` or `:tags` options are passed, only the mentioned attributes and tags are allowed and nothing else.
 
 ```ruby
 sanitize @article.body, tags: %w(table tr td), attributes: %w(id class style)
diff --git a/guides/source/active_record_migrations.md b/guides/source/active_record_migrations.md
index ad069a112e..0b84001ca5 100644
--- a/guides/source/active_record_migrations.md
+++ b/guides/source/active_record_migrations.md
@@ -423,21 +423,23 @@ change_column :products, :part_number, :text
 ```
 
 This changes the column `part_number` on products table to be a `:text` field.
+Note that `change_column` command is irreversible.
 
 Besides `change_column`, the `change_column_null` and `change_column_default`
-methods are used specifically to change a not null constraint and default values of a
-column.
+methods are used specifically to change a not null constraint and default
+values of a column.
 
 ```ruby
 change_column_null :products, :name, false
-change_column_default :products, :approved, false
+change_column_default :products, :approved, from: true, to: false
 ```
 
 This sets `:name` field on products to a `NOT NULL` column and the default
-value of the `:approved` field to false.
+value of the `:approved` field from true to false.
 
-TIP: Unlike `change_column` (and `change_column_default`), `change_column_null`
-is reversible.
+Note: You could also write the above `change_column_default` migration as
+`change_column_default :products, :approved, false`, but unlike the previous
+example, this would make your migration irreversible.
 
 ### Column Modifiers
 
diff --git a/guides/source/active_support_instrumentation.md b/guides/source/active_support_instrumentation.md
index 373dbbb9aa..e49abc41f4 100644
--- a/guides/source/active_support_instrumentation.md
+++ b/guides/source/active_support_instrumentation.md
@@ -321,17 +321,6 @@ Action Mailer
 }
 ```
 
-Active Resource
---------------
-
-### request.active_resource
-
-| Key            | Value                |
-| -------------- | -------------------- |
-| `:method`      | HTTP method          |
-| `:request_uri` | Complete URI         |
-| `:result`      | HTTP response object |
-
 Active Support
 --------------
 
diff --git a/guides/source/association_basics.md b/guides/source/association_basics.md
index 0f909e9861..c0fa3cfd04 100644
--- a/guides/source/association_basics.md
+++ b/guides/source/association_basics.md
@@ -2354,13 +2354,13 @@ associations, public methods, etc.
 Creating a car will save it in the `vehicles` table with "Car" as the `type` field:
 
 ```ruby
-Car.create color: 'Red', price: 10000
+Car.create(color: 'Red', price: 10000)
 ```
 
 will generate the following SQL:
 
 ```sql
-INSERT INTO "vehicles" ("type", "color", "price") VALUES ("Car", "Red", 10000)
+INSERT INTO "vehicles" ("type", "color", "price") VALUES ('Car', 'Red', 10000)
 ```
 
 Querying car records will just search for vehicles that are cars:
diff --git a/guides/source/generators.md b/guides/source/generators.md
index 14f451cbc9..32bbdc554a 100644
--- a/guides/source/generators.md
+++ b/guides/source/generators.md
@@ -503,6 +503,14 @@ Adds a specified source to `Gemfile`:
 add_source "http://gems.github.com"
 ```
 
+This method also takes a block:
+
+```ruby
+add_source "http://gems.github.com" do
+  gem "rspec-rails"
+end
+```
+
 ### `inject_into_file`
 
 Injects a block of code into a defined position in your file.
diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md
index 79d4393f32..a091f84fb0 100644
--- a/guides/source/getting_started.md
+++ b/guides/source/getting_started.md
@@ -298,6 +298,7 @@ Rails.application.routes.draw do
 
   # The priority is based upon order of creation:
   # first created -> highest priority.
+  # See how all your routes lay out with "rake routes".
   #
   # You can have the root of your site routed with "root"
   # root 'welcome#index'
diff --git a/guides/source/i18n.md b/guides/source/i18n.md
index 31682464ee..272a0e3623 100644
--- a/guides/source/i18n.md
+++ b/guides/source/i18n.md
@@ -210,7 +210,7 @@ This approach has almost the same set of advantages as setting the locale from t
 
 Getting the locale from `params` and setting it accordingly is not hard; including it in every URL and thus **passing it through the requests** is. To include an explicit option in every URL, e.g. `link_to(books_url(locale: I18n.locale))`, would be tedious and probably impossible, of course.
 
-Rails contains infrastructure for "centralizing dynamic decisions about the URLs" in its [`ApplicationController#default_url_options`](http://api.rubyonrails.org/classes/ActionDispatch/Routing/Mapper/Base.html#method-i-default_url_options), which is useful precisely in this scenario: it enables us to set "defaults" for [`url_for`](http://api.rubyonrails.org/classes/ActionDispatch/Routing/UrlFor.html#method-i-url_for) and helper methods dependent on it (by implementing/overriding this method).
+Rails contains infrastructure for "centralizing dynamic decisions about the URLs" in its [`ApplicationController#default_url_options`](http://api.rubyonrails.org/classes/ActionDispatch/Routing/Mapper/Base.html#method-i-default_url_options), which is useful precisely in this scenario: it enables us to set "defaults" for [`url_for`](http://api.rubyonrails.org/classes/ActionDispatch/Routing/UrlFor.html#method-i-url_for) and helper methods dependent on it (by implementing/overriding `default_url_options`).
 
 We can include something like this in our `ApplicationController` then:
 
diff --git a/guides/source/rails_on_rack.md b/guides/source/rails_on_rack.md
index 117017af90..1e2fe94010 100644
--- a/guides/source/rails_on_rack.md
+++ b/guides/source/rails_on_rack.md
@@ -58,22 +58,6 @@ class Server < ::Rack::Server
 end
 ```
 
-Here's how it loads the middlewares:
-
-```ruby
-def middleware
-  middlewares = []
-  middlewares << [::Rack::ContentLength]
-  Hash.new(middlewares)
-end
-```
-
-The following table explains the usage of the loaded middlewares:
-
-| Middleware              | Purpose                                                                           |
-| ----------------------- | --------------------------------------------------------------------------------- |
-| `Rack::ContentLength`   | Counts the number of bytes in the response and set the HTTP Content-Length header |
-
 ### `rackup`
 
 To use `rackup` instead of Rails' `rails server`, you can put the following inside `config.ru` of your Rails application's root directory:
@@ -81,8 +65,6 @@ To use `rackup` instead of Rails' `rails server`, you can put the following insi
 ```ruby
 # Rails.root/config.ru
 require ::File.expand_path('../config/environment', __FILE__)
-
-use Rack::ContentLength
 run Rails.application
 ```
 
@@ -327,8 +309,6 @@ Resources
 
 * [Official Rack Website](http://rack.github.io)
 * [Introducing Rack](http://chneukirchen.org/blog/archive/2007/02/introducing-rack.html)
-* [Ruby on Rack #1 - Hello Rack!](http://m.onkey.org/ruby-on-rack-1-hello-rack)
-* [Ruby on Rack #2 - The Builder](http://m.onkey.org/ruby-on-rack-2-the-builder)
 
 ### Understanding Middlewares