I love the smell of UnrealEd crashing in the morning. – tarquin
UnrealKismet
From Unreal Wiki, The Unreal Engine Documentation Site
UnrealKismet is a Visual Scripting system within the UDK that allows artists that don't possess programming knowledge to create scripted behavior from within levels in a relatively quick and intuitive manner. It has been called a rapid prototype editor, as it is powerful enough in many cases to be used to test out complete gameplay concepts without writing a single line of UnrealScript code.
Sequence Objects
Each sequence object is a self-contained black box which performs a single purpose. The types of sequence objects available are:
- Actions - These are objects which perform some action on the Actors in your level.
- Conditions - These do not actually affect the level, but the control flow of your sequence. They make decisions on which output to fire depending on some condition.
- Variables - These objects simply store information of a particular type for use by an Event, Action or Condition.
- Events - These are objects which create an 'input' to your sequence, possibly from an Actor in the game. A common example is the Level Loaded event which fires when the level begins.
For a basic understanding of UnrealKismet, it is highly recommended to visit the UDN pages on the topic, as they are among the best Epic has to offer.