In a table of contents the page number first starts from the "Introduction" page. I want it to start from "Abstract" using \section not \chapter. How do I achieve that?

\documentclass[11pt]{article}
\begin{document}
\pagenumbering{roman}
\section*{Abstract}
\section*{Acknowledgment}
\tableofcontents
\pagenumbering{arabic}
\section{Introduction}

• Welcome to TeX.SX. Please do not post only fragments of code. The sharelatex tag is irrelevant here – user31729 Jan 18 '16 at 17:35

By default, \section* adds nothing to the ToC. You have to add it manually:

\documentclass{article}
\begin{document}

\pagenumbering{roman}
\section*{Abstract}
\clearpage

\section*{Acknowledgment}
\clearpage

\tableofcontents
\clearpage

\pagenumbering{arabic}
\section{Introduction}

\end{document}


Here are some additional things you need to note:

• \pagenumbering resets the page counter and changes the page display. However, in your example you've set it to roman and arabic on the same page. Only the last reference will be used as page numbering is only visible during page shipout.

• Adding section-specific content to the ToC is achieved using

\addcontentsline{toc}{section}{<stuff>}


where <stuff> includes your \section* title. You may decide to align this (unnumbered) title with the other (numbered) titles or not. Abstract is not aligned and flush left, while Acknowledgement is aligned with the other section titles.

• I've added \clearpage between every section so as to highlight the effect of the page numbering. This may differ from your actual implementation. Consider the effect of \pagenumbering though, as mentioned above.

Pagenumbering changes are only effective after a \clearpage. If the Table of Contents shouldn't be numbered with roman numbers, remove the second \clearpage before \tableofcontents. But \section* will not make an entry to the ToC at all.

Better use \section{Abstract} etc. and suppress the numbering with \secnumdepth{-1}.

\documentclass[11pt]{article}
\begin{document}
\pagenumbering{roman}
\setcounter{secnumdepth}{-1}
\section{Abstract}
\section{Acknowledgment}
\setcounter{secnumdepth}{3} % Reenable the numbering of sections etc.