Throughout this book you will see file sizes specified with an assortment of units. For example: 42 kB, 42 Mb, 42 GiB, 42 G, 42 GiB.
Without an explanation this may seem confusing, random, and inconsistent. However, there is a method to this madness:
The unit used in discussion preceding/following an example is consistent with the convention used in the example
Without any scope or context, binary prefixes are used (e.g., 1024 KiB, 35565 MiB)
For additional literature on why this necessary, I refer you to Appendix A, Appendix: Man Pages