\documentclass{article}
\usepackage{multido}
\begin{document}
\paragraph{Basic Types}
\multido{}{10}{\TeX\ }

\multido{\d=2pt+3pt}{5}{\d, }

\multido{\n=2+3}{10}{\n, }

\multido{\i=2+-3}{10}{\i, }

\multido{\r=2+3.04}{6}{\r, }

\multido{\n=2.00+-3.05}{8}{\n, }

\paragraph{Backwards}
\multido{}{-10}{\TeX\ }

\multido{\d=2pt+3pt}{-5}{\d, }

\multido{\n=2+3}{-10}{\n, }

\multido{\i=2+-3}{-10}{\i, }

\multido{\r=2+3.04}{-6}{\r, }

\multido{\n=2.00+-3.05}{-8}{\n, }

\paragraph{Pre-Increment}
\mmultido{}{10}{\TeX\ }

\mmultido{\d=2pt+3pt}{5}{\d, }

\mmultido{\n=2+3}{10}{\n, }

\mmultido{\i=2+-3}{10}{\i, }

\mmultido{\r=2+3.04}{6}{\r, }

\mmultido{\n=2.00+-3.05}{8}{\n, }

\paragraph{Ignore Space}
\multido{}{10}{\TeX}   .nospace

\paragraph{Nesting}
\multido{\iA=1+1}{4}{\multido{\iB=1+1}{4}{(\iA\iB)}}

\paragraph{Shortcut}
\newcount\myc
\multido{\n=2+3}{10}{\myc=\n\relax\ifnum\myc>10 Done!\multidostop\else\n\ keep going!\fi,}

\paragraph{Grouping}
\def\iyai{before}
\iyai
\multido{\iyai=2+1}{4}{\iyai, }
\iyai

\paragraph{Nogrouping}
\def\iyai{before}
\iyai
\Multido{\iyai=2+1}{4}{\iyai, }
\iyai

\paragraph{Munging variables}
\mmultido{\i=0+2}{10}{\i, }

compare to
\myc=0\relax
\mmultido{\i=0+2}{10}{\i, \advance\myc1\relax\ifnum\myc>1\myc=0\relax\def\i{0}\relax\fi}

\paragraph{Fixed Point Arithmetic}

\def\answer{Nothing}
Add...\fpAdd{1.75}{0.25}{\answer}
The answer is \answer.

\def\answer{Nothing}
Subtract...\fpSub{1.75}{0.25}{\answer}
The answer is \answer.

\end{document}

\paragraph{Checking variables}
\MultidoCheckNames
\mmultido{\i=0+2}{10}{\i, }
