2da, Two Dimensional Array, files are some of the core files used by the game. They are used to define anything from models for the player character's models, to the spells and force powers used by many characters in the game. The most popular  2da editor is the one built in to kotor tool. You can find the 2da files in the 2da.bif. Please note, however, that not all 2da files found in the games archives are used in game, some are left-over from NeverWinter Nights.

2DA example

A typical 2DA file.