diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index e0bfdb8f3e5f0226a831e1bb0f476c94771389ca..aa92343f76665cd521c3729f93a730aaed7d1da3 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -21,7 +21,7 @@ module ClassMethods
       # Generates all the attribute related methods for columns in the database
       # accessors, mutators and query methods.
       def define_attribute_methods # :nodoc:
-        # Use a mutex; we don't want two thread simaltaneously trying to define
+        # Use a mutex; we don't want two thread simultaneously trying to define
         # attribute methods.
         @attribute_methods_mutex.synchronize do
           return if attribute_methods_generated?
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
index 2859fb31e8ef4e1ae8de04bc25b627b07b557d70..c0a21115716fd5f942d0806254b09d6c61699984 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb
@@ -21,7 +21,7 @@ def table_name_length
       # limit is enforced by rails and Is less than or equal to
       # <tt>index_name_length</tt>. The gap between
       # <tt>index_name_length</tt> is to allow internal rails
-      # opreations to use prefixes in temporary opreations.
+      # operations to use prefixes in temporary operations.
       def allowed_index_name_length
         index_name_length
       end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
index 73c80a322023803aa091b6621cccb0560802f951..2b6685499ab6e98ae0e9508bd7aaceff506ce679 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
@@ -78,7 +78,7 @@ def initialize(connection, parent, options = {})
         @joinable  = options.fetch(:joinable, true)
       end
 
-      # This state is necesarry so that we correctly handle stuff that might
+      # This state is necessary so that we correctly handle stuff that might
       # happen in a commit/rollback. But it's kinda distasteful. Maybe we can
       # find a better way to structure it in the future.
       def finishing?
diff --git a/activerecord/lib/active_record/explain.rb b/activerecord/lib/active_record/explain.rb
index 3135465dfe056231f44af4ae4e38949eccc68372..15736575a2283930933df9c10c439ed209c2f2b5 100644
--- a/activerecord/lib/active_record/explain.rb
+++ b/activerecord/lib/active_record/explain.rb
@@ -9,7 +9,7 @@ def collecting_queries_for_explain # :nodoc:
       yield
       return current[:available_queries_for_explain]
     ensure
-      # Note that the return value above does not depend on this assigment.
+      # Note that the return value above does not depend on this assignment.
       current[:available_queries_for_explain] = original
     end
 
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 1de7ee084642d435576962c3606d3d4a52832bf5..cfe0ed80b85f3a87713ed9da3e248c4d391e2a81 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -193,7 +193,7 @@ def test_finding_with_includes_on_has_many_association_with_same_include_include
     end
   end
 
-  def test_finding_with_includes_on_has_one_assocation_with_same_include_includes_only_once
+  def test_finding_with_includes_on_has_one_association_with_same_include_includes_only_once
     author = authors(:david)
     post = author.post_about_thinking_with_last_comment
     last_comment = post.last_comment
diff --git a/activerecord/test/cases/attribute_methods_test.rb b/activerecord/test/cases/attribute_methods_test.rb
index c503c21e27bfab5beff5f4e0cf88bffadba7d911..648596b82855c6b0fbf8296086e3227f0f186fdd 100644
--- a/activerecord/test/cases/attribute_methods_test.rb
+++ b/activerecord/test/cases/attribute_methods_test.rb
@@ -159,8 +159,8 @@ def test_array_content
   end
 
   def test_read_attributes_before_type_cast
-    category = Category.new({:name=>"Test categoty", :type => nil})
-    category_attrs = {"name"=>"Test categoty", "id" => nil, "type" => nil, "categorizations_count" => nil}
+    category = Category.new({:name=>"Test category", :type => nil})
+    category_attrs = {"name"=>"Test category", "id" => nil, "type" => nil, "categorizations_count" => nil}
     assert_equal category_attrs , category.attributes_before_type_cast
   end
 
diff --git a/activerecord/test/cases/batches_test.rb b/activerecord/test/cases/batches_test.rb
index acb8b5f56278e93f74adf761e3a023cdaa2dd90e..87559925e7d707cb64218989bd6f7de79f0faed5 100644
--- a/activerecord/test/cases/batches_test.rb
+++ b/activerecord/test/cases/batches_test.rb
@@ -11,7 +11,7 @@ def setup
     Post.count('id') # preheat arel's table cache
   end
 
-  def test_each_should_excecute_one_query_per_batch
+  def test_each_should_execute_one_query_per_batch
     assert_queries(Post.count + 1) do
       Post.find_each(:batch_size => 1) do |post|
         assert_kind_of Post, post
diff --git a/activerecord/test/cases/dup_test.rb b/activerecord/test/cases/dup_test.rb
index fe105b9d227235cec71619463985ee71c75f9207..dbf6005a67c4a64c23d525a9679262e242b6d2de 100644
--- a/activerecord/test/cases/dup_test.rb
+++ b/activerecord/test/cases/dup_test.rb
@@ -110,7 +110,7 @@ def test_dup_after_initialize_callbacks
     def test_dup_validity_is_independent
       repair_validations(Topic) do
         Topic.validates_presence_of :title
-        topic = Topic.new("title" => "Litterature")
+        topic = Topic.new("title" => "Literature")
         topic.valid?
 
         duped = topic.dup
diff --git a/activerecord/test/cases/nested_attributes_test.rb b/activerecord/test/cases/nested_attributes_test.rb
index 94837341fcd89505a3467bb46624925b611f1d47..7042d7f4b6c1addde99110eca4c4b92b97b8641d 100644
--- a/activerecord/test/cases/nested_attributes_test.rb
+++ b/activerecord/test/cases/nested_attributes_test.rb
@@ -167,7 +167,7 @@ def test_reject_if_with_blank_nested_attributes_id
   def test_first_and_array_index_zero_methods_return_the_same_value_when_nested_attributes_are_set_to_update_existing_record
     Man.accepts_nested_attributes_for(:interests)
     man = Man.create(:name => "John")
-    interest = man.interests.create :topic => 'gardning'
+    interest = man.interests.create :topic => 'gardening'
     man = Man.find man.id
     man.interests_attributes = [{:id => interest.id, :topic => 'gardening'}]
     assert_equal man.interests.first.topic, man.interests[0].topic