Although the Finder goes out of its way to display bundles as files, it does provide some tools for peeking into package contents. You can use the Finder to view and install localizations for individual applications. You can also open the bundle directly and examine the entire application bundle.
Unix commands make no attempt to disguise the true nature of application bundles—the very concept of bundles is alien to a Unix system. Terminal is another good way to reveal the contents of an application.
In the Try It Out example that follows, you use both Finder and Terminal to examine the contents of the Mail Application's bundle.
In the Finder, select /Applications/Mail.
Control-click the Mail application's icon. A contextual menu appears.
Select Get Info from the contextual menu. A panel appears that resembles Figure 5-1
Open the Languages section by clicking its disclosure triangle. The panel resizes to reveal a list of languages, as seen in Figure 5-2.
Uncheck one of the languages in the list; it's a good idea to pick a language that you aren't currently using. We chose to turn off Spanish.
Close the Get Info panel.
Control-click the Mail icon ...