Each set of constants to be managed is placed in a ZEBRA titles bank. These banks start with a fixed Database header that carries information about the validity range and type of the data. This is followed by the user data itself. ZEBRA includes TZ, a system that can read these banks from a free-format, easy to edit, text file ( called a titles file). Titles banks can also be stored in the database, indeed this is where most banks will be stored; only non-standard ones will normally be found in titles files.
During initialisation, the system reads an arbitrary number of titles files as directed by the user (e.g., via ``titles'' commands in a cmd file). These banks are NOT read into the standard IQ/RQ array; instead they are stored in a separate memory with the array names ICONS/RCONS (collectively referred to as xCONS). This COMMON is defined in the include file mt.inc. Other banks are drawn from the database on demand and are also placed in the ICONS/RCONS array.