Building custom formats
INITEX can also be used to create custom formats to speed up
typesetting, especially for LATEX documents that use lots of packages.
Let's say you have a file called thesis.tex.
Edit this file, cut out everything before \begin{document}
and paste it into a new file called, say, thesis.ini.
Set the current folder by selecting ``TEX ...'', locating
thesis.ini and hitting Cancel.
Select INITEX, type ``&LaTeX thesis.ini\dump''
and create thesis.fmt in the current folder.
Add a new top line in thesis.tex containing %&thesis.
Now when you typeset thesis.tex will load thesis.fmt
and you should see a significant reduction in the typesetting time.