2.1.1.1 The Current Readtable

Several readtables describing different syntaxes can exist, but at any given time only one, called the current readtable, affects the way in which expressions[2] are parsed into objects by the Lisp reader. The current readtable in a given dynamic environment is the value of *readtable* in that environment. To make a different readtable become the current readtable, *readtable* can be assigned or bound.