\documentclass{article}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{latexsym}


\begin{document}

  \title{A sample article}
  \author{Claus Schubert}
  \maketitle



  \begin{abstract}
    This is the abstract of the following article.
  \end{abstract}

  \section{Heading}
     This is the first section.

  \section{Next Heading}
     This is the next section.


\end{document}