It's pretty complicated to explain how the software is actually working in details, but as far as I know and used the application there is:
The ePSXe loads the BIOS file and then all the plug-ins along with the PS1 ISO or disc and boots the game.
You can find more at the Wikipedia website: https://en.wikipedia.org/wiki/EPSXe
It is a PlayStation 1 emulator that enables you to play the games on your PC.
It is an application that enhances the experience of the game.
ZX Spectrum Emulator - Emulate the original 16k, 48k, 128k, +2 models.
It's pretty complicated to explain how the software is actually working in details, but as far as I know and used the application there is:
The ePSXe loads the BIOS file and then all the plug-ins along with the PS1 ISO or disc and boots the game.
You can find more at the Wikipedia website: https://en.wikipedia.org/wiki/EPSXe