This documentation is for version 3.0 of iTerm2. Documentation for version 2.1.4 is here.
iTerm2 should require little explanation for users accustomed to terminal emulators. Even if you are an experienced user, take the time to read through the highlights section of this document. It will familiarize you with some features of iTerm2 that you may not have seen in other terminal emulators that can make a real difference in the way you work.
A printable version of the documentation is also available.