Now that we have the application properly localized to use resource files, it's time to put the finishing stamp on it by code-signing the application.
Code signing is very similar to signing an important document in front of a notary public. The notary is there to make sure that you are the proper person who is supposed to sign the document and that you did in fact sign it by making you do it before them. In essence, the notary is a third party that verifies who you say you are and that you didn't fake the signature on the document.
In the case of Code signing, you are literally submitting the application that you have just created to RIM and, by entering your login and password, promising that your application doesn't do anything bad.
Most of the interesting objects and methods in the BlackBerry SDK require code signing in order to use them. They work fine in the simulator, but if you were to try to load the applications onto an actual device the loader would...