Some comments are contained, lines starting with. Often used for file references or to display text. Values are plain text without quotation marks. They are composed of the three RGB values (ranging from 0 to 255), divided by commas and without blanks. is also often reduced to 4 or 2 decimal places. The console command SaveIniFiles creates a configuration file, where all these are cut down to 4 decimal places, while the command GetINISetting puts them out with only 2. They can only have the valid values of 0 and 1, where 0 means 'false' or 'disabled', and 1 means 'true' or 'enabled'.
There are several types of variables, determining the possible values one can have.
It normally remains unchanged, though the Fallout: New Vegas version is overwritten with default values each time the game is started via Steam. It is then saved in the user's My Game directory. The Fallout.ini, together with the FalloutPrefs.ini, is created when for the first time the launcher of the game is started.