The use of ROM-based software is a feature that is almost unique to the BBC Micro. This practical book covers all aspects of using, designing and choosing ROM-based software and the ancillaries that this involves. It shows how the paged ROM system and ROM filing system work, and provides programming examples to help readers produce their own sideways ROMs using EPROMs and sideways RAM. In addition, the large amount of available paged ROM-associated hardware, such as ROM boards, sideways ROM and EPROM programmers, and ROM-based software, including toolkits, monitors and utilities, are examined in detail, along with second processor compatability.