This guide steps you through setting up your environment, getting familiar with the Titanium architecture and getting started with your first project.
Download and Install Titanium. For mobile, you'll also need to install the Apple iPhone SDK or the Android SDK to build and run your application within Titanium.
We've put all our APIs into code examples in a project we call 'The Kitchen Sink'. We also have some other sample projects that you can fire up in Titanium Developer based on your interests.