Hi, Here are some remarks from my last reading of expl3.pdf (r1439). 1. Concerning the terminology of "functions". Maybe it's worth mentioning at some point that the word function is used in opposition to variable, not to macro: theses two objects (functions and variables) remain actually macros, and TeX a macro language (like make or C preprocessor as opposed to C). Currently, I expect only experienced TeX programmers will look into expl3 so they should be mistaken, but for the TeX-programming newcomer, the peculiarities of a macro language are often so difficult to understand, that IMO expl3 should state clearly that it doesn't magically turn TeX into a classical programming language, and that the terms function/variable are only a convention, an not to be understood in their usual meaning. (Same for the terminology that a "function" "returns" something, though I'm not sure I've seen in in expl3.pdf or only in source3e.pdf). 2. Still terminology: sometimes "execution" is used when the most accurate term would be expansion (eg on the top of page 7). Again, I expect an experienced TeX programmer to understand what is actually meant, but I think that for the sake of less experienced readers, such language approximations should be avoided, or the document should include a warning that sometimes "execution" will be used as a generic term for execution-or-expansion-or-both. 3. Thanks a lot for the revised section 5 and the new section 6! 4. It is probably useful to mention that for further information on the expl3 modules, source3.pdf is the reference. Also, a link to the project site (or its papers/ page) would probably be welcome. Manuel.