The term "Disc 1CHD Work" refers to a specific type of game release format. CHD (Compressed HACK Disk) files are associated with emulator usage, allowing for the compression of game data to fit on a single disc or to facilitate digital distribution. The mention of "Disc 1CHD Work" in relation to the Spanish release of Metal Gear Solid hints at a specialized version of the game, possibly intended for a particular market or distribution method.

"CHD?" Snake whispered into his mic. "Sounds like a storage format."

You cannot convert a raw .bin file to CHD directly for PS1 games; you use the .cue file. If you downloaded a ROM set that only has a .bin file, you need to create a .cue file.

To convert your files, you'll need a tool called chdman (often bundled with MAME or available in standalone batch scripts).