G2's developer's environment refers to the default set of features that are available when you use G2 under a development license. You use these features to define objects, as well as their properties and behaviors, and to organize them into a knowledge base (or KB). We use the word knowledge to mean information that is structured and specified so that a running G2 can reason about it.
The set of knowledge that a running G2 contains is called the current KB. After G2 starts, it always has a current KB. That is, a portion of G2's memory is always reserved to hold the objects that currently represent the knowledge you have collected and organized. At all times, the current KB contains a set of system tables, which represent your current preferences for how G2 works with the KB.
G2 executes, or runs, the current KB. You can start, pause, resume, reset, and restart (that is, reset and start as one command) the current KB.
You can save the current KB's knowledge into a new or existing KB file. G2 does not alter a KB file until you save the current KB into it.
You can also load or merge a KB into G2 from a KB file that you previously saved. You can load one KB, or more than one KB, into G2 at the same time. You can also load and store specially partitioned KBs called modularized KBs.
For more information about the features of KBs, see Chapter 3, Knowledge Bases.