Your data reduction strategy will be more effective if you have an idea of how big the data and map file sizes will
be on disk. Also, it will help you estimate just how many files you can backup to tape. In this appendix, we will
discuss file sizes in bytes, which are 8 bits in size, rather than “blocks,” which can vary in size between different
computers. Inside , the definition of “byte” is perverted, but all systems now use a 1024-byte (8192 bit)
“block.”