The core of the OS needs 64 KB ROM. On the CPC6128 it needs a ROM expansion or similar. Compatible products are EPROM-cards, the [[X-MEM]], [[MegaFlash]], [[Inicron ROM-RAM-Box|ROM-RAM-BOX]], [[SYMBiFACE II|SYMBiFACE II]], [[Ramcard 128|RAMcard]], Jareks [[CPC.Flash|Flash-ROM]], [[MegaROM]] or similar products. If you don't own such a card, you can take a look at '''FutureOS''' by using a compatible CPC Emulator ([[JavaCPC|JavaCPC]], [[WinCPC|WinCPC]], [[CaPriCe|Caprice]], [[WinApe|WinApe]], [[!CPCemu|CPCEmu]], [[Arnold]], [[Sugarbox]]) or others.
The core of the OS itself is executed directly in (Flash-)ROM or [[Dobbertin EPROM 224|EPROM]] (in four 16 KB blocks). The support of the M4 SD card needs a fifth ROM of 16 KB though. The OS allows jumps between the ROMs with the help of a little common area. Therefore the numbers of the four (five) 16 KB ROMs are hardcoded and the jumps are very quick. But never mind, adapting ROM number is done by the installation software anyway. Applications like ROManager do also set all that ROM numbers automatically right. Further parts of the OS can be loaded from media on demand if needed. Examples are the multitasking manager [[Caruh ]] and the UI/menu framework CBM.
'''FutureOS''' uses 2 KB (&B800...&BFFF) of the first 64 KB; the remaining RAM is available to applications. Additional RAM can be reserved for DIRectory buffering. Furthermore the OS uses memory management (up to 4 MB), file-handling and specialized Low/Mid/High-level routines and functions to access and manage the hardware.