\documentclass{beamer}

% Theme
% For a list of supported themes, see
% https://deic.uab.cat/~iblanes/beamer_gallery/index_by_theme.html
\usetheme{Madrid}


% Custom color (here blue)
% Uncomment next  two lines to define custom color for current theme
% \definecolor{UBCblue}{rgb}{0.04706, 0.13725, 0.26667}
% \usecolortheme[named=UBCblue]{structure}


\usepackage{ucs}
\usepackage[utf8x]{inputenc}
\usepackage[greek,english]{babel}
\newcommand{\en}{\selectlanguage{english}}
\newcommand{\gr}{\selectlanguage{greek}}

\begin{document}
\en


\title{Title}
\author{Author name}
\institute{Applied Economics and Data Analysis \\ Department of Economics \\ University of Patras \\ University Campus, Rio, 26504, Patras, GREECE}
\date{\today}


\maketitle

\begin{frame}
\frametitle{Description of slide content}  
An item list:
\begin{itemize}
\item A long sentence to show 	
\item an item 
\item an item 
\item another item 
\end{itemize}
\end{frame}




\begin{frame}
\frametitle{Some cool content}  
\begin{itemize}
	\item item 1 	
	\item item 2 
	\item item 3 
	\item item 4 
\end{itemize}
\end{frame}

\end{document}