2.3.5 Downloaded and cached .deb archive files

If you have manually downloaded package files to your disk (which is not absolutely necessary, see above for the description of dpkg-ftp or APT), then after you have installed the packages, you can remove the .deb files from your system.

If APT is used, these files are cached in the /var/cache/apt/archives directory. You may erase them after installation (apt-get clean) or copy them to another machine's /var/cache/apt/archives directory to save downloading during subsequent installations.