Every OurBigBook macro is either block or inline:
  • a block macro is one that takes up the entire line when rendered
    All block macros start with a capital letter, e.g. \H for headers.
  • and an inline macro is one that goes inside of a line.
    Every inline macro starts with a lowercase letter e.g. \a for links.
Some macros have both a block and an inline version, and like any other macro, those are differentiated by capitalization: