Cadence Allegro file Extensions and what they contain.

***********************************************
.brd - Board database file–typically the printed circuit board (PCB) design file that you add symbols and a net list to when designing the board.
.dra - Drawing file–graphics that can be graphically edited and used to create the binary symbols that are used in the .brd file.
.mdd - Module definitions–sections of a board design that include package symbols and logical connections.
.psm - Package symbol, footprint.
.bsm - Mechanical symbol (board symbol) that gets added to a board with no logic attached.
.osm - Format symbol, (other symbol)–typically graphics, notes,drawing format, notes, logo’s.
.ssm - Shape symbol–when a pad is an irregular shape (not a circle, square, rectangle, and so on).
.fsm - Flash symbol–used to define a thermal relief pad. There is an editor that helps you automatically create these.
.pad - A padstack.
.scr - Script or macro file–an ASCII text file containing Allegro commands that can be replayed to reproduce the same results as if you were selecting those commands.
.tech - Technology file–ASCII file of constraints and design rules.
.mcm - Multi-chip Module File (APD) A design file similar to an Allegro.brd file, but different technology
.txt - Text file, such as that used for parameters. Device files are .txt that contain the definition of a logical device including device type, package symbol, pincount, functions, and swappability.
.jrl - A journal file contains a record of events—menu picks,keyboard, and so on—which are recorded for each session in Allegro. .tag - Keeps track of the last board worked on in your current directory.Without it, Allegro will open up a new board file.
.INI - This file keeps track of the path your working file is in. The.INI file also keeps track of the window location, the toolbar,and the status of whether the Control Panel is docked and it's location. DO NOT EDIT THIS FILE, if you are having problems with Allegro. This file can be deleted as a form of troubleshooting. The file will be recreated automatically.
.geo - This file remembers the location of forms the last time they were used and places the same type of form in the same location the next time it is used. DO NOT EDIT THIS FILE!
.color - Color view—defines which subclass graphics will be visible or invisible.This file is automatically created when an artwork film control is defined or can be user defined.