The file mylatex.ltx permits you to create a format that
pre-loads a set of package files (and/or other macros) that you
regularly use. In some circumstances, this can be a great
advantage (though on an ordinarily fast modern computer on the
desktop, gains will be limited). The general scheme is to
initialise your usage by a command of the form: latex -ini
mylatex.ltx <document> whick will create a format file
mylatex.fmt, which you then use as: latex -fmt=mylatex
<document>
