Update README.md

README.md

@@ -63,7 +63,7 @@ Vernier can be enabled globally within a Ruby script or application:
 require "vernier/autorun
 ```
 
-For example, adding this to a Rails applications `config/application.rb` will enable Vernier during boot and output a recording when exited.
+For example, adding this to a Rails application's `config/application.rb` will enable Vernier during boot and output a recording when exited.
 
 #### Block of code