layout

\setlength{\parindent}{1.5em}           % erstzeileneinzug
\setlength{\parskip}{0.5\baselineskip}  % absatzabstand

packages

% utf8 assumed as default since 2018
\usepackage[utf8]{inputenc}

% enables hyphenation w/ ümläüts
% sometimes not needed, when other packages already require it
\usepackage[T1]{fontenc}

makeatletter

in tex "category codes" ("catcodes") specify how characters are handled. "normal characters" have catcode 11. @ has catcode 11 in class and package files and 12 in text files. this is commonly used to write private macros, which cannot easily be used and overwritten by users.

\makeatletter % changes the catcode of @ to 11
can use macro names w/ '@' in their names
\makeatother % changes the catcode of @ back to 12

tools

rubber runs latex until indexes are stable, also supports makeindex, bibtex and others, produces dvi by default.

# switch output to pdf file
rubber --pdf <file>
# clean intermediate files
rubber --clean <file>
# clean intermediate and target file (pdf)
rubber --clean --pdf <file>