Subtitle in latex

There is no direct command to define subtitle in latex. But you can define the \subtitle command using titling package. To do this just insert the following code in the preamble of the latex file.

\usepackage{titling}
\newcommand{\subtitle}[1]{%
  \posttitle{%
    \par\end{center}
    \begin{center}\large#1\end{center}
    \vskip0.5em}%
}

And then you can define subtitle using the following command.

\subtitle{Subtitle Here}

This will show the subtitle bellow your title when you use \maketitle command.

Minimum working example

Code

\documentclass[10pt,a4paper]{article}
\usepackage{lipsum}

\usepackage{titling}
\newcommand{\subtitle}[1]{%
	\posttitle{%
		\par\end{center}
	\begin{center}\large#1\end{center}
	\vskip0.1em}}%

\title{This is the title of the document}
\subtitle{This is subtitle}
\author{Apurba Paul}
\date{January 08, 2013}

\begin{document}
	\maketitle

	Body of the document. 

	\lipsum[1]
	
\end{document}

Output

Hope this will help.

Cheers
A.Paul