diff --git a/CHANGELOG.md b/CHANGELOG.md
index efdfb23c..de156c60 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,7 @@
 master
 ===
 
-* i18n was accidently duplicating requests for extension-based template (file.es.html)
+* i18n was accidentally duplicating requests for extension-based template (file.es.html)
 
 # 4.3.0.rc.3
 
@@ -15,7 +15,7 @@ master
 * Update Rubocop and apply new lint rules
 * Do not create unnecessary array in IgnoreDescriptor (#2183)
 * Fix reload of watched sources with destination_dir (#2190)
-* Fix localisation and recursion issues of Traversal::parent. (#2188)
+* Fix localization and recursion issues of Traversal::parent. (#2188)
 * Use EnhancedHash for partial locals (#2169)
 
 # 4.3.0.rc.1
@@ -30,11 +30,11 @@ master
 * Clear lazy map after resolving Tilt templates (#2132)
 * Fix ignore of I18n files (#2143)
 * Fix redirect destination lookup (#2140) 
-* Add LD-JSON to MinifyJavascript content types allowed to be compressed (#2138)
+* Add LD-JSON to MinifyJavaScript content types allowed to be compressed (#2138)
 * chmod before closing file to fix compatibility with JRuby (#2133)
 * Keeps full file path for chained templates (#2117) 
 * Use i18n fallbacks when looking up localized paths (#2116)
-* Compat with latest rails/activsupport < 5.2 (#2095)
+* Compat with latest rails/activesupport < 5.2 (#2095)
 * Update "Port in use"-message for PreviewServer (#2089) 
 * I18n: Keep fragment and query in url_for (#2062)
 * Add support for locale suffixes to link_to (#2065)
@@ -46,7 +46,7 @@ master
 
 # 4.2.0
 
-Fix #1951. A failed build would "clean" all files in build. Possibly breaking change, "clean" and "after_build" are only run for sucessful builds.
+Fix #1951. A failed build would "clean" all files in build. Possibly breaking change, "clean" and "after_build" are only run for successful builds.
 
 # 4.1.14
 
diff --git a/README.md b/README.md
index 4b91d4de..67e7434d 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ middleman server
 
 The preview server allows you to build your site, by modifying the contents of the `source` directory, and see your changes reflected in the browser at: `http://localhost:4567/`
 
-To get started, simply develop as you normally would by building HTML, CSS, and Javascript in the `source` directory. When you're ready to use more complex templates, simply add the templating engine's extension to the file and start writing in that format.
+To get started, simply develop as you normally would by building HTML, CSS, and JavaScript in the `source` directory. When you're ready to use more complex templates, simply add the templating engine's extension to the file and start writing in that format.
 
 For example, say I am working on a stylesheet at `source/stylesheets/site.css` and I'd like to start using Sass. I would rename the file to `source/stylesheets/site.css.scss` and Middleman will automatically begin processing that file as Sass. The same would apply to CoffeeScript (`.js.coffee`), Haml (`.html.haml`) and any other templating engine you might want to use.
 
@@ -57,7 +57,7 @@ Finally, you will want to build your project into a stand-alone site. From the p
 middleman build
 ```
 
-This will compile your templates and output a stand-alone site which can be easily hosted or delivered to your client. The build step can also compress images, employ Javascript & CSS dependency management, minify Javascript & CSS and run additional code of your choice. Take a look at the `config.rb` file to see some of the most common extensions which can be activated.
+This will compile your templates and output a stand-alone site which can be easily hosted or delivered to your client. The build step can also compress images, employ JavaScript & CSS dependency management, minify JavaScript & CSS and run additional code of your choice. Take a look at the `config.rb` file to see some of the most common extensions which can be activated.
 
 ## Learn More
 
diff --git a/middleman-core/features/coffee-script.feature b/middleman-core/features/coffee-script.feature
index cf30bcd2..6ef1498d 100644
--- a/middleman-core/features/coffee-script.feature
+++ b/middleman-core/features/coffee-script.feature
@@ -1,5 +1,5 @@
 Feature: Support coffee-script
-  In order to offer an alternative when writing Javascript
+  In order to offer an alternative when writing JavaScript
 
   Scenario: Rendering coffee script
     Given the Server is running at "coffeescript-app"
diff --git a/middleman-core/features/ignore_already_minified.feature b/middleman-core/features/ignore_already_minified.feature
index d24d8109..c7a0652f 100644
--- a/middleman-core/features/ignore_already_minified.feature
+++ b/middleman-core/features/ignore_already_minified.feature
@@ -1,4 +1,4 @@
-Feature: CSS and Javascripts which are minify shouldn't be re-minified
+Feature: CSS and JavaScripts which are minify shouldn't be re-minified
 
   Scenario: JS files containing ".min" should not be re-compressed
     Given an empty app
diff --git a/middleman-core/features/minify_javascript.feature b/middleman-core/features/minify_javascript.feature
index f97a1f54..e9ebcbe8 100644
--- a/middleman-core/features/minify_javascript.feature
+++ b/middleman-core/features/minify_javascript.feature
@@ -1,4 +1,4 @@
-Feature: Minify Javascript
+Feature: Minify JavaScript
   In order reduce bytes sent to client and appease YSlow
 
   Scenario: Rendering inline js with the feature disabled
diff --git a/middleman-core/features/page-id.feature b/middleman-core/features/page-id.feature
index b67d7659..7c1c31e2 100644
--- a/middleman-core/features/page-id.feature
+++ b/middleman-core/features/page-id.feature
@@ -11,7 +11,7 @@ Feature: Page IDs
     And I should see 'URL5: <a href="/implicit.html">Imp</a>'
     And I should see 'URL6: <a href="/folder/foldern.html">Foldern</a>'
     And I should see 'URL7: <a href="/feed.xml">Feed</a>'
-    And I should see "URL8: /fourty-two.html"
+    And I should see "URL8: /forty-two.html"
 
     When I go to "/fm.html"
     Then I should see "I am: frontmatter"
@@ -46,7 +46,7 @@ Feature: Page IDs
     And I should see "URL2: /2.html"
     And I should see 'URL3: <a href="/3.html">Hi</a>'
     And I should see 'URL4: <a href="/overwrites/from-default.html">Sym</a>'
-    And I should see "URL8: /fourty-two.html"
+    And I should see "URL8: /forty-two.html"
     And I should see 'URL9: <a href="/implicit.html">Imp</a>'
     And I should see 'URL10: <a href="/folder/foldern.html">Foldern</a>'
     And I should see 'URL11: <a href="/feed.xml">Feed</a>'
diff --git a/middleman-core/fixtures/asset-hash-minified-app/config.rb b/middleman-core/fixtures/asset-hash-minified-app/config.rb
index 94db1542..96f8266c 100644
--- a/middleman-core/fixtures/asset-hash-minified-app/config.rb
+++ b/middleman-core/fixtures/asset-hash-minified-app/config.rb
@@ -1,5 +1,5 @@
 configure :build do
-  # Minify Javascript on build
+  # Minify JavaScript on build
   activate :minify_javascript
   activate :asset_hash
 end
diff --git a/middleman-core/fixtures/env-app/source/stylesheets/site.css.scss b/middleman-core/fixtures/env-app/source/stylesheets/site.css.scss
index bcb115c5..67ce83e4 100644
--- a/middleman-core/fixtures/env-app/source/stylesheets/site.css.scss
+++ b/middleman-core/fixtures/env-app/source/stylesheets/site.css.scss
@@ -1,3 +1,3 @@
 body {
-  backgroud: red;
+  background: red;
 }
diff --git a/middleman-core/fixtures/generator-test/config.rb b/middleman-core/fixtures/generator-test/config.rb
index 03711c11..f90ab441 100644
--- a/middleman-core/fixtures/generator-test/config.rb
+++ b/middleman-core/fixtures/generator-test/config.rb
@@ -42,7 +42,7 @@
 configure :production do
   # activate :minify_css
 
-  # Minify Javascript
+  # Minify JavaScript
   # activate :minify_javascript
 
   # Enable cache buster
diff --git a/middleman-core/fixtures/page-id-app/source/fourty-two.html.erb b/middleman-core/fixtures/page-id-app/source/forty-two.html.erb
similarity index 100%
rename from middleman-core/fixtures/page-id-app/source/fourty-two.html.erb
rename to middleman-core/fixtures/page-id-app/source/forty-two.html.erb
diff --git a/middleman-core/lib/middleman-core/application.rb b/middleman-core/lib/middleman-core/application.rb
index 370395c3..9f80a1f6 100644
--- a/middleman-core/lib/middleman-core/application.rb
+++ b/middleman-core/lib/middleman-core/application.rb
@@ -439,7 +439,7 @@ module Middleman
     #
     # @deprecated Prefer accessing settings through "config".
     #
-    # @param [Symbol] key Name of the attribue
+    # @param [Symbol] key Name of the attribute
     # @param value Attribute value
     # @return [void]
     def set(key, value = nil, &block)
diff --git a/middleman-core/lib/middleman-core/core_extensions.rb b/middleman-core/lib/middleman-core/core_extensions.rb
index e38be937..a5b5f82e 100644
--- a/middleman-core/lib/middleman-core/core_extensions.rb
+++ b/middleman-core/lib/middleman-core/core_extensions.rb
@@ -100,10 +100,10 @@ Middleman::Extensions.register :minify_css do
   Middleman::Extensions::MinifyCss
 end
 
-# MinifyJavascript compresses JS
+# MinifyJavaScript compresses JS
 Middleman::Extensions.register :minify_javascript do
   require 'middleman-core/extensions/minify_javascript'
-  Middleman::Extensions::MinifyJavascript
+  Middleman::Extensions::MinifyJavaScript
 end
 
 # GZIP assets and pages during build
diff --git a/middleman-core/lib/middleman-core/extension.rb b/middleman-core/lib/middleman-core/extension.rb
index b1ae7137..028c837f 100644
--- a/middleman-core/lib/middleman-core/extension.rb
+++ b/middleman-core/lib/middleman-core/extension.rb
@@ -204,7 +204,7 @@ module Middleman
       #   expose_to_application global_name: :local_name
       # @example with Array:
       #   expose_to_application :method1, :method2
-      # @param [Array<Sumbol>, Hash<Symbol, Symbol>] symbols An optional list of symbols representing instance methods to exposed.
+      # @param [Array<Symbol>, Hash<Symbol, Symbol>] symbols An optional list of symbols representing instance methods to exposed.
       # @return [void]
       def expose_to_application(*symbols)
         self.exposed_to_application ||= {}
@@ -224,7 +224,7 @@ module Middleman
       #   expose_to_config global_name: :local_name
       # @example with Array:
       #   expose_to_config :method1, :method2
-      # @param [Array<Sumbol>, Hash<Symbol, Symbol>] symbols An optional list of symbols representing instance methods to exposed.
+      # @param [Array<Symbol>, Hash<Symbol, Symbol>] symbols An optional list of symbols representing instance methods to exposed.
       # @return [void]
       def expose_to_config(*symbols)
         self.exposed_to_config ||= {}
@@ -244,7 +244,7 @@ module Middleman
       #   expose_to_template global_name: :local_name
       # @example with Array:
       #   expose_to_template :method1, :method2
-      # @param [Array<Sumbol>, Hash<Symbol, Symbol>] symbols An optional list of symbols representing instance methods to exposed.
+      # @param [Array<Symbol>, Hash<Symbol, Symbol>] symbols An optional list of symbols representing instance methods to exposed.
       # @return [void]
       def expose_to_template(*symbols)
         self.exposed_to_template ||= {}
diff --git a/middleman-core/lib/middleman-core/extensions/gzip.rb b/middleman-core/lib/middleman-core/extensions/gzip.rb
index 54839f4a..2d15158a 100644
--- a/middleman-core/lib/middleman-core/extensions/gzip.rb
+++ b/middleman-core/lib/middleman-core/extensions/gzip.rb
@@ -1,7 +1,7 @@
 # This extension Gzips assets and pages when building.
 # Gzipped assets and pages can be served directly by Apache or
 # Nginx with the proper configuration, and pre-zipping means that we
-# can use a more agressive compression level at no CPU cost per request.
+# can use a more aggressive compression level at no CPU cost per request.
 #
 # Use Nginx's gzip_static directive, or AddEncoding and mod_rewrite in Apache
 # to serve your Gzipped files whenever the normal (non-.gz) filename is requested.
diff --git a/middleman-core/lib/middleman-core/extensions/minify_css.rb b/middleman-core/lib/middleman-core/extensions/minify_css.rb
index 71868e4f..d5537d3d 100644
--- a/middleman-core/lib/middleman-core/extensions/minify_css.rb
+++ b/middleman-core/lib/middleman-core/extensions/minify_css.rb
@@ -57,7 +57,7 @@ class Middleman::Extensions::MinifyCss < ::Middleman::Extension
     end
 
     # Rack interface
-    # @param [Rack::Environmemt] env
+    # @param [Rack::Environment] env
     # @return [Array]
     def call(env)
       status, headers, response = @app.call(env)
diff --git a/middleman-core/lib/middleman-core/extensions/minify_javascript.rb b/middleman-core/lib/middleman-core/extensions/minify_javascript.rb
index c6a7dcb8..0d1a71b6 100644
--- a/middleman-core/lib/middleman-core/extensions/minify_javascript.rb
+++ b/middleman-core/lib/middleman-core/extensions/minify_javascript.rb
@@ -2,8 +2,8 @@ require 'active_support/core_ext/object/try'
 require 'middleman-core/contracts'
 require 'memoist'
 
-# Minify Javascript Extension
-class Middleman::Extensions::MinifyJavascript < ::Middleman::Extension
+# Minify JavaScript Extension
+class Middleman::Extensions::MinifyJavaScript < ::Middleman::Extension
   option :inline, false, 'Whether to minify JS inline within HTML files'
   option :ignore, [], 'Patterns to avoid minifying'
   option :compressor, proc {
@@ -49,7 +49,7 @@ class Middleman::Extensions::MinifyJavascript < ::Middleman::Extension
     end
 
     # Rack interface
-    # @param [Rack::Environmemt] env
+    # @param [Rack::Environment] env
     # @return [Array]
     def call(env)
       status, headers, response = @app.call(env)
diff --git a/middleman-core/lib/middleman-core/file_renderer.rb b/middleman-core/lib/middleman-core/file_renderer.rb
index 5e7e9a36..46e8ae78 100644
--- a/middleman-core/lib/middleman-core/file_renderer.rb
+++ b/middleman-core/lib/middleman-core/file_renderer.rb
@@ -32,7 +32,7 @@ module Middleman
     def render(locs, opts, context, &block)
       path = @path.dup
 
-      # Detect the remdering engine from the extension
+      # Detect the rendering engine from the extension
       extension = File.extname(path)
       engine = extension[1..-1].to_sym
 
diff --git a/middleman-core/lib/middleman-core/meta_pages/sitemap_tree.rb b/middleman-core/lib/middleman-core/meta_pages/sitemap_tree.rb
index 4ba89350..66c9b4ca 100644
--- a/middleman-core/lib/middleman-core/meta_pages/sitemap_tree.rb
+++ b/middleman-core/lib/middleman-core/meta_pages/sitemap_tree.rb
@@ -59,7 +59,7 @@ module Middleman
 
         if path_parts.size == 1
           sitemap_class = SitemapResource
-          # Allow special sitemap resources to use custom metadata view calsses
+          # Allow special sitemap resources to use custom metadata view classes
           sitemap_class = resource.meta_pages_class if resource.respond_to? :meta_pages_class
 
           @children[first_part] = sitemap_class.new(resource)
diff --git a/middleman-core/lib/middleman-core/preview_server.rb b/middleman-core/lib/middleman-core/preview_server.rb
index d4cd1c2a..22ff0c23 100644
--- a/middleman-core/lib/middleman-core/preview_server.rb
+++ b/middleman-core/lib/middleman-core/preview_server.rb
@@ -212,7 +212,7 @@ module Middleman
         @cli_options[key] || config[key]
       end
 
-      # Trap some interupt signals and shut down smoothly
+      # Trap some interrupt signals and shut down smoothly
       # @return [void]
       def register_signal_handlers
         %w[INT HUP TERM QUIT].each do |sig|
diff --git a/middleman-core/lib/middleman-core/preview_server/server_information_callback_proxy.rb b/middleman-core/lib/middleman-core/preview_server/server_information_callback_proxy.rb
index e913612d..819d18e8 100644
--- a/middleman-core/lib/middleman-core/preview_server/server_information_callback_proxy.rb
+++ b/middleman-core/lib/middleman-core/preview_server/server_information_callback_proxy.rb
@@ -7,7 +7,7 @@ module Middleman
     # * server name
     # * site_addresses
     #
-    # All information is "dupped" and the callback is not meant to be used to
+    # All information is "duped" and the callback is not meant to be used to
     # modify these information.
     class ServerInformationCallbackProxy
       attr_reader :server_name, :port, :site_addresses, :listeners
diff --git a/middleman-core/lib/middleman-core/sitemap/extensions/traversal.rb b/middleman-core/lib/middleman-core/sitemap/extensions/traversal.rb
index 26017e8d..de7d2570 100644
--- a/middleman-core/lib/middleman-core/sitemap/extensions/traversal.rb
+++ b/middleman-core/lib/middleman-core/sitemap/extensions/traversal.rb
@@ -28,8 +28,8 @@ module Middleman
           # Does the current page has the name of an index file?
           is_index = current_page == index_file
           # Is the `current_page` in the traversal root?
-          # Note: `traversal_root` is `/` for non localised pages and `/[lang]/` for
-          # localised pages.
+          # Note: `traversal_root` is `/` for non localized pages and `/[lang]/` for
+          # localized pages.
           at_traversal_root = !(child_path =~ /^#{traversal_root}#{current_page}$/).nil?
 
           # Check that we have any path parts left after the pop because if we
@@ -66,8 +66,8 @@ module Middleman
           # E.g. `parts == ['en', 'blog']`, we try to find: `/en/blog.html`
           file_by_parts.call(parts)
 
-          # Try to find an non-localised parent instead if `traversal_root`
-          # indicates the path is localised and there are still more parts
+          # Try to find an non-localized parent instead if `traversal_root`
+          # indicates the path is localized and there are still more parts
           # remaining, and return it.
           # E.g. `parts == ['en', 'blog']`, we try to find: `/blog.html`
           if traversal_root != '/' && parts.length > 1
@@ -80,7 +80,7 @@ module Middleman
           parts.pop if is_index
           index_by_parts.call(parts)
 
-          # Lastly, check for an non-localised index index file in the path
+          # Lastly, check for an non-localized index index file in the path
           # above `current_page`'s path and return it.
           # E.g. `parts == ['en', 'blog']`, we try to find: `/index.html`
           if traversal_root == "#{parts.first}/"
diff --git a/middleman-core/lib/middleman-core/sitemap/store.rb b/middleman-core/lib/middleman-core/sitemap/store.rb
index 616d5f61..5a1cea84 100644
--- a/middleman-core/lib/middleman-core/sitemap/store.rb
+++ b/middleman-core/lib/middleman-core/sitemap/store.rb
@@ -121,7 +121,7 @@ module Middleman
         rebuild_resource_list!(:"registered_new_manipulator_#{name}")
       end
 
-      # Rebuild the list of resources from scratch, using registed manipulators
+      # Rebuild the list of resources from scratch, using registered manipulators
       # @return [void]
       Contract Symbol => Any
       def rebuild_resource_list!(name)
diff --git a/middleman-core/lib/middleman-core/sources/source_watcher.rb b/middleman-core/lib/middleman-core/sources/source_watcher.rb
index 30bc6dd3..4212b5a2 100644
--- a/middleman-core/lib/middleman-core/sources/source_watcher.rb
+++ b/middleman-core/lib/middleman-core/sources/source_watcher.rb
@@ -301,7 +301,7 @@ module Middleman
       [valid_updates, valid_removes]
     end
 
-    # Convert a path to a file resprentation.
+    # Convert a path to a file representation.
     #
     # @param [Pathname] path The path.
     # @return [Middleman::SourceFile]
diff --git a/middleman-core/lib/middleman-core/util/files.rb b/middleman-core/lib/middleman-core/util/files.rb
index c2a76d0b..e1503eb0 100644
--- a/middleman-core/lib/middleman-core/util/files.rb
+++ b/middleman-core/lib/middleman-core/util/files.rb
@@ -6,7 +6,7 @@ module Middleman
 
     module_function
 
-    # Get a recusive list of files inside a path.
+    # Get a recursive list of files inside a path.
     # Works with symlinks.
     #
     # @param path Some path string or Pathname
diff --git a/middleman-core/spec/middleman-core/core_extensions/data_spec.rb b/middleman-core/spec/middleman-core/core_extensions/data_spec.rb
index 34f7206f..64ae8222 100644
--- a/middleman-core/spec/middleman-core/core_extensions/data_spec.rb
+++ b/middleman-core/spec/middleman-core/core_extensions/data_spec.rb
@@ -87,7 +87,7 @@ describe Middleman::CoreExtensions::Data::DataStore do
     end
 
     context 'given path matches callback data' do
-      it 'returns value of calback lambda' do
+      it 'returns value of callback lambda' do
         @subject.callbacks :foo, -> { { 'bar' => 'baz' } }
         @subject.callbacks :wu, -> { %i[tang clan] }