PHYZZX is a macropackage which is designed to make typing papers destined for Physical Review or Nuclear Physics as simple as possible. In addition it allows you to type letters and produce memos without knowing much about the way TEX works.
The first question which arises at this point is What is a
macropackage ?, or for that matter What is a macro?.
Despite the name a macro is not something eaten on a
macrobiotic diet.
It is a name for a simple thing.
Unfortunately, this name has
been carefully designed by computerniks
to strike terror into the heart of occasional users and keep them
in their place. (There is nothing more annoying than an
uppity occasional user.)
Basically a macro is a way of defining an entry in a dictionary
which is kept in the guts of the computer.
The computer uses this dictionary to
find the meaning of words which have been defined
using the control sequence
def.
A macropackage is, as the name implies, a package of macros (or
definitions of commands) which we can use to give complicated
formatting instructions to TEX without having to go
to the trouble of typing everything out each time we want to
give the same instruction.
It follows from this discussion that PHYZZX is just a collection of definitions which tell TEX to do a well defined set of things to make the text which follows look just the way you want it to look. The best thing about a macropackage is that once it is written you only have to know what happens when you issue a given instruction; you don't have to know how it is made to happen. Although each of the commands which appear in the macropackage cause apparently simple things to happen, making them happen can get quite involved if you try to use the PLAIN version of TEX.