Having used LaTeX (using TeXworks with pdfLaTeX) for around a year now, I decided it would be a useful (/interesting) exercise to learn TeX, since this is the fundamental language underlying LaTeX (and therefore allows for the redefinition of LaTeX macros, the coding of which I believe would have to be done in TeX [correct if wrong]). I am learning from a copy of the TeXBook (an excellent read), which provides many examples etc, encouraging the reader to try things out for themself.
The primary way of compiling TeX which Knuth gives (which is as far as I know is the standard way), is to type the document out in a text editor, which is then handed to the TeX 'engine', which compiles the document. However, since there are many examples and exercises in the book to try, I have taken to simply trying out the commands in the TeXworks editor and then compiling (using pdfLaTeX), as this is the easiest and quickest way to see the result.
So far, I have found no problems with doing this, and to me this made sense, since (in my head), LaTeX is built upon TeX, adding in no new fundamentals, thus any command which does something in TeX, should do the same in LaTeX.
However recently I have been reading more into the exact differences between LaTeX and TeX, and it seems as though the two are more different than I first assumed. For the most part this doesn't bother me, since whilst some TeX commands have been re-designed for LaTeX (eg the
\it command, replaced by
\textit), the TeX commands themselves still do work, so in theory, I could still type a document out in plain TeX, then compile it with pdfLaTeX, and produce a correct result. However, I saw something troubling here which suggested that there are some TeX commands which assume different meanings which interpreted by LaTeX.
Please could someone give some examples of these commands, and if possible, give any other justification as to why plain TeX should not be used within LaTeX.
Any help is greatly appreciated! :)
Postscript: I am aware that TeXworks also provides the option of compiling with pdfTeX, however this would remove the macros made by LaTeX (such as the
\section command), thus making life harder again. My question is more one of principle rather than actually suggesting that I might try and typeset in TeX using LaTeX.