diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
index 34627dfaf91b6..2a8807fb78647 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
@@ -193,7 +193,7 @@ def connection
     #     :database  => "path/to/dbfile"
     #   )
     #
-    # Also accepts keys as strings (for parsing from yaml for example):
+    # Also accepts keys as strings (for parsing from YAML for example):
     #
     #   ActiveRecord::Base.establish_connection(
     #     "adapter" => "sqlite",
diff --git a/activesupport/lib/active_support/json/decoding.rb b/activesupport/lib/active_support/json/decoding.rb
index c58001f49fe91..fdb219dbf77dc 100644
--- a/activesupport/lib/active_support/json/decoding.rb
+++ b/activesupport/lib/active_support/json/decoding.rb
@@ -31,7 +31,7 @@ def convert_json_to_yaml(json) #:nodoc:
                 if json[pos..scanner.pos-2] =~ DATE_REGEX
                   # found a date, track the exact positions of the quotes so we can remove them later.
                   # oh, and increment them for each current mark, each one is an extra padded space that bumps
-                  # the position in the final yaml output
+                  # the position in the final YAML output
                   total_marks = marks.size
                   times << pos+total_marks << scanner.pos+total_marks
                 end
diff --git a/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml b/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml
index 79d5721a534fe..fe80872a1684e 100644
--- a/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml
+++ b/railties/test/fixtures/about_yml_plugins/bad_about_yml/about.yml
@@ -1 +1 @@
-# an empty yaml file - any content in here seems to get parsed as a string
\ No newline at end of file
+# an empty YAML file - any content in here seems to get parsed as a string
\ No newline at end of file
diff --git a/railties/test/generators/generator_test_helper.rb b/railties/test/generators/generator_test_helper.rb
index c99df6e2d36c9..41ddeb7d71913 100644
--- a/railties/test/generators/generator_test_helper.rb
+++ b/railties/test/generators/generator_test_helper.rb
@@ -86,19 +86,19 @@ def test_truth
     # don't complain, test/unit
   end
 
-  # Instantiates the Generator
+  # Instantiates the Generator.
   def build_generator(name, params)
     Rails::Generator::Base.instance(name, params)
   end
 
-  # Runs the create command (like the command line does)
+  # Runs the +create+ command (like the command line does).
   def run_generator(name, params)
     silence_generator do
       build_generator(name, params).command(:create).invoke!
     end
   end
 
-  # Silences the logger temporarily and returns the output as a String
+  # Silences the logger temporarily and returns the output as a String.
   def silence_generator
     logger_original = Rails::Generator::Base.logger
     myout = StringIO.new
@@ -108,7 +108,7 @@ def silence_generator
     myout.string
   end
 
-  # asserts that the given controller was generated.
+  # Asserts that the given controller was generated.
   # It takes a name or symbol without the <tt>_controller</tt> part and an optional super class.
   # The contents of the class source file is passed to a block.
   def assert_generated_controller_for(name, parent = "ApplicationController")
@@ -117,44 +117,44 @@ def assert_generated_controller_for(name, parent = "ApplicationController")
     end
   end
 
-  # asserts that the given model was generated.
+  # Asserts that the given model was generated.
   # It takes a name or symbol and an optional super class.
-  # the contents of the class source file is passed to a block.
+  # The contents of the class source file is passed to a block.
   def assert_generated_model_for(name, parent = "ActiveRecord::Base")
     assert_generated_class "app/models/#{name.to_s.underscore}", parent do |body|
       yield body if block_given?
     end
   end
 
-  # asserts that the given helper was generated.
-  # It takes a name or symbol without the <tt>_helper</tt> part
-  # the contents of the module source file is passed to a block.
+  # Asserts that the given helper was generated.
+  # It takes a name or symbol without the <tt>_helper</tt> part.
+  # The contents of the module source file is passed to a block.
   def assert_generated_helper_for(name)
     assert_generated_module "app/helpers/#{name.to_s.underscore}_helper" do |body|
       yield body if block_given?
     end
   end
 
-  # asserts that the given functional test was generated.
+  # Asserts that the given functional test was generated.
   # It takes a name or symbol without the <tt>_controller_test</tt> part and an optional super class.
-  # the contents of the class source file is passed to a block.
+  # The contents of the class source file is passed to a block.
   def assert_generated_functional_test_for(name, parent = "ActionController::TestCase")
     assert_generated_class "test/functional/#{name.to_s.underscore}_controller_test",parent do |body|
       yield body if block_given?
     end
   end
 
-  # asserts that the given unit test was generated.
+  # Asserts that the given unit test was generated.
   # It takes a name or symbol without the <tt>_test</tt> part and an optional super class.
-  # the contents of the class source file is passed to a block.
+  # The contents of the class source file is passed to a block.
   def assert_generated_unit_test_for(name, parent = "ActiveSupport::TestCase")
     assert_generated_class "test/unit/#{name.to_s.underscore}_test", parent do |body|
       yield body if block_given?
     end
   end
 
-  # asserts that the given file was generated.
-  # the contents of the file is passed to a block.
+  # Asserts that the given file was generated.
+  # The contents of the file is passed to a block.
   def assert_generated_file(path)
     assert_file_exists(path)
     File.open("#{RAILS_ROOT}/#{path}") do |f|
@@ -168,9 +168,9 @@ def assert_file_exists(path)
       "The file '#{RAILS_ROOT}/#{path}' should exist"
   end
 
-  # asserts that the given class source file was generated.
+  # Asserts that the given class source file was generated.
   # It takes a path without the <tt>.rb</tt> part and an optional super class.
-  # the contents of the class source file is passed to a block.
+  # The contents of the class source file is passed to a block.
   def assert_generated_class(path, parent = nil)
     # FIXME: Sucky way to detect namespaced classes
     if path.split('/').size > 3
@@ -187,9 +187,9 @@ def assert_generated_class(path, parent = nil)
     end
   end
 
-  # asserts that the given module source file was generated.
+  # Asserts that the given module source file was generated.
   # It takes a path without the <tt>.rb</tt> part.
-  # the contents of the class source file is passed to a block.
+  # The contents of the class source file is passed to a block.
   def assert_generated_module(path)
     # FIXME: Sucky way to detect namespaced modules
     if path.split('/').size > 3
@@ -206,18 +206,18 @@ def assert_generated_module(path)
     end
   end
 
-  # asserts that the given css stylesheet file was generated.
+  # Asserts that the given css stylesheet file was generated.
   # It takes a path without the <tt>.css</tt> part.
-  # the contents of the stylesheet source file is passed to a block.
+  # The contents of the stylesheet source file is passed to a block.
   def assert_generated_stylesheet(path)
     assert_generated_file("public/stylesheets/#{path}.css") do |body|
       yield body if block_given?
     end
   end
 
-  # asserts that the given yaml file was generated.
+  # Asserts that the given YAML file was generated.
   # It takes a path without the <tt>.yml</tt> part.
-  # the parsed yaml tree is passed to a block.
+  # The parsed YAML tree is passed to a block.
   def assert_generated_yaml(path)
     assert_generated_file("#{path}.yml") do |body|
       yaml = YAML.load(body)
@@ -226,18 +226,18 @@ def assert_generated_yaml(path)
     end
   end
 
-  # asserts that the given fixtures yaml file was generated.
+  # Asserts that the given fixtures yaml file was generated.
   # It takes a fixture name without the <tt>.yml</tt> part.
-  # the parsed yaml tree is passed to a block.
+  # The parsed YAML tree is passed to a block.
   def assert_generated_fixtures_for(name)
     assert_generated_yaml "test/fixtures/#{name.to_s.underscore}" do |yaml|
       yield yaml if block_given?
     end
   end
 
-  # asserts that the given views were generated.
+  # Asserts that the given views were generated.
   # It takes a controller name and a list of views (including extensions).
-  # The body of each view is passed to a block
+  # The body of each view is passed to a block.
   def assert_generated_views_for(name, *actions)
     actions.each do |action|
       assert_generated_file("app/views/#{name.to_s.underscore}/#{action}") do |body|
@@ -262,7 +262,7 @@ def assert_skipped_migration(name)
     assert !File.exist?(migration_file), "should not create migration #{migration_file}"
   end
 
-  # asserts that the given resource was added to the routes.
+  # Asserts that the given resource was added to the routes.
   def assert_added_route_for(name)
     assert_generated_file("config/routes.rb") do |body|
       assert_match /map.resources :#{name.to_s.underscore}/, body,
@@ -270,7 +270,7 @@ def assert_added_route_for(name)
     end
   end
 
-  # asserts that the given methods are defined in the body.
+  # Asserts that the given methods are defined in the body.
   # This does assume standard rails code conventions with regards to the source code.
   # The body of each individual method is passed to a block.
   def assert_has_method(body, *methods)
@@ -280,7 +280,7 @@ def assert_has_method(body, *methods)
     end
   end
 
-  # asserts that the given column is defined in the migration
+  # Asserts that the given column is defined in the migration.
   def assert_generated_column(body, name, type)
     assert_match /t\.#{type.to_s} :#{name.to_s}/, body, "should have column #{name.to_s} defined"
   end