This is pdfTeX, Version 3.14159-13d (Web2C 7.3.1) (format=pdflatex 2001.9.17)  7 DEC 2002 21:34
**hierarchy.tex
(hierarchy.tex[/usr/share/texmf/pdftex/config/pdftex.cfg]
LaTeX2e <2000/06/01>
Babel <v3.7h> and hyphenation patterns for american, french, german, ngerman, i
talian, portuges, spanish, swedish, nohyphenation, loaded.
! Undefined control sequence.
l.1 \section
            {Class Hierarchy}
? 
! Emergency stop.
l.1 \section
            {Class Hierarchy}
End of file on the terminal!

 
Here is how much of TeX's memory you used:
 4 strings out of 50606
 45 string characters out of 691828
 44176 words of memory out of 1500001
 3070 multiletter control sequences out of 10000+25000
 3640 words of font info for 14 fonts, out of 400000 for 1000
 16 hyphenation exceptions out of 1000
 5i,0n,1p,41b,7s stack positions out of 1500i,500n,1500p,50000b,5000s
!  ==> Fatal error occurred, the output PDF file not finished!