\frametitle{Environment Variables}
\begin{columns}
\begin{column}{0.48\columnwidth}
\begin{definition}[Definition]\label{sec:orgaa2da59}
Variables that define the environment in which your programs run.
\end{definition}
\begin{block}{Common Variables}
\begin{center}
\begin{tabular}{ll}
Var & Meaning\\
\hline
\texttt{PATH} & Command search\\
\texttt{HOME} & Home directory\\
\texttt{USER} & Username\\
\texttt{PWD} & Current dir\\
\end{tabular}
\end{center}
\end{block}
\end{column}
\begin{column}{0.48\columnwidth}
\begin{block}{Usage Examples}
\begin{verbatim}
# Display
echo $USER

# Set (local to shell)
MY_VAR="value"

# Export (available to child procs)
export MY_VAR="value"

# View all
env | head
\end{verbatim}
\end{block}
\end{column}
\end{columns}
