Tables

\usepackage{booktabs}

\begin{table}
\begin{tabular}{ccc}
\toprule
\textbf{a} & \textbf{b} & \textbf{c} \\ 
\midrule
1 & 2 & 3 \\ 
\bottomrule
\end{tabular}
\end{table}

A good reference for how to make beautiful tables, particularly when they're complicated and hierarchical: http://www.ece.cmu.edu/~pueschel/teaching/guides/guide-tables.pdf