\documentclass{article}
\begin{document}
\begin{tabbing}
  First Tab Stop \= Second \= Third \= \kill
  one \> two \> three \> four \\
  new tab\ \= two \> \a'{e}\a`{e} \`(accent commands)\\
  new tab\ \= two \> aeae \\
  one \> two \> three \> four
\end{tabbing}

\newcommand\lenrule[1]{\makebox[#1]{%
    \rule{.4pt}{4pt}\hrulefill\rule{.4pt}{4pt}}}
\begin{tabbing}
  dd\quad \= \hspace{.55\linewidth} \= \kill
  pc \> Pica = 12pt \> \lenrule{1pc} \\
  cc \> Cicero = 12dd \> \lenrule{1cc} \\
  cm \> Centimeter = 10mm \> \lenrule{1cm} \\
\end{tabbing}

\begin{tabbing}
    \quad \= \quad \= \quad \= \hspace{5cm} \= \kill
    \textbf{program} test \> \> \> \> \texttt{some text here} \\
    \textbf{var} \\
    \> $i$ : \textbf{integer}; \> \> \> \texttt{...} \\
    \> $b$ : \textbf{boolean}; \\
    \textbf{begin} \\
    \> $i:=1$; \> \> \> \texttt{...} \\
    \> $b:=\texttt{true}$; \\
    \> \textbf{while} $i<15$ \textbf{do} \\
    \> \> $i:=i+1$; \\
    \> \> $b:=\textbf{not}\ b$; \> \> \texttt{some text here} \\
    \> \textbf{od} \\
    \textbf{end}
\end{tabbing}

\end{document}