When you’re working on the first edition of your website in a development environment, managing
the site and its source code is pretty straightforward. You have only a single version of the site’s source, making it easy to maintain. However, as soon as you put your site in production, you now have two versions of it: one running in the production environment and the one you use for development.This makes it difficult to keep things synchronized. For example, you probably use a different database and connection string in your production environment. You’re also likely to use different e-mail addresses for the e-mail that is sent by the site. Finally, you may want to disable sending the error e-mails from the Global.asax files in a development environment. If you make all of thesechanges in the code directly when you put your site on a production server, there’s a fair chance that you’ll overwrite some settings during the next update, which can lead to unwanted results.