DBPF
Database Packed File (DBPF) is a proprietary archive format used in many Maxis developed games, including The Sims 2, SimCity 4 and Spore. DBPF files are similar to Zip files, as they hold other files inside them which are usually compressed. All plugins for SimCity 4 (excluding the SC4 Extra Cheats.dll) are DBPF files, the file name's extension is irrelevant.
DBPF files can be identified by opening the file in notepad, or preferably a hex editor, as the first 4 characters/bytes will be the letters DBPF. If a file in the plugins folder does not start with these 4 letters the game will not load them, however the Reader will. This means that if you want to disable a plugin you can open the DBPF file in a hex editor and change the first byte to something other than 44 (in Hexadecimal) (D) and the game will not load the plugin, but you will still be able to edit it in the reader (saving the disabled plugin with the reader will not re enable it, to re enable you must change the first byte back to 44 (hexadecimal)).
Entries may be compressed with RefPack compression depending on their entry data.
For an examination of the Spore DBPF format, see Spore DBPF.
