The last option that we will learn about is using Android's debug output to LogCat. LogCat is an Android logger that can be accessed through the adb tool, and it is available in Eclipse as well. Logging, in general, is a way to output text that a developer needs to see but should stay hidden from the user.
To open the LogCat tab, go to Window | Show View | Others… and search for LogCat.
If an Android device is already connected, LogCat will immediately show some log messages. The following screenshot shows an example of what a LogCat output looks like:
The log messages have the following attributes: