\documentclass{article}
\usepackage{array}
\newcolumntype{C}{>{$}c<{$}}
\newcolumntype{L}{>{$}l<{$}}
\newcolumntype{R}{>{$}r<{$}}

\begin{document}

\section{New Column types}
\begin{tabular}{|p{1in}|m{1in}|b{1in}|}\hline
Lorem ipsum dolor sit amet, consectetur adipisicing elit &
Lorem ipsum dolor sit amet, consectetur adipisicing elit &
Lorem ipsum dolor sit amet, consectetur adipisicing elit \\\hline
Lorem ipsum dolor sit amet, consectetur adipisicing elit &
Lorem ipsum dolor sit amet, consectetur adipisicing elit &
Lorem ipsum dolor sit amet, consectetur adipisicing elit \\
\hline
\end{tabular}

\begin{tabular}{|>{[}l<{]}|>{[}c<{]}|>{[}r<{]}|}
left & center & right\\
\end{tabular}


\section{Math columns}
\begin{tabular}{cC}
word & a+b \\
word & a+b \\
\end{tabular}

\begin{equation}
z=
\begin{array}{Cc}
word & a+b \\
word & a+b \\
\end{array}
\end{equation}
\section{Special variations of hline}
Tables
\begin{tabular}[t]{l}
with no\\ hline \\ commands \\ used
\end{tabular} versus

tables
\begin{tabular}[t]{|l|}
\hline
with\\ hline \\ commands \\ 
\hline
\end{tabular} used.


tables
\begin{tabular}[t]{|l|}
\firsthline
with\\ hline \\ commands \\ 
\lasthline
\end{tabular} used.



\end{document}