Join PDFs together using LaTeX

There is a package called pdfpages, its usage can be found here.

\documentclass{article}% or something else
\usepackage{pdfpages}
\begin{document}
\includepdf[pages=-]{paper1}
\includepdf[pages=-]{paper2}

\end{document}

This is a sample code copied from here.

Under Unix-like systems, after installing texlive and pdfjam, we could always join PDFs together by such command:

pdfjoin 1.pdf 2.pdf 3.pdf --outfile combine.pdf

see pdfjoin –help for more information.