LaTeX evidently has a syntax based on Pascal, but this syntax is not explicitly part of LaTeX, only something that the developers of LaTeX use internally I think you are probably referring to the pascal-ish comments that were in the sorces for latex209 and some remain in the `oldcomments' sections in the current sources. Leslie Lamport used those while designing the original latex algorithms but they are not really used now. Most of them have been removed as they had (even in the days of 2.09) got out of sync with the actual code implementation and so were more confusing than helpful. David