What's the difference between flashplugin-installer and adobe-flashplugin?

I've just downloaded both packages to inspect them, the process for comparing the packages can be found on the bottom.

adobe-flashplugin

It contains the Flash player library and configures itself as default for Internet browsers. It was only available for 32-bit systems, but since October 2011 a 64-bit version is available too for Ubuntu Lucid and later. This can be installed from the partner repository, see also How do I enable the "partner" repository?

flashplugin-installer

It extracts the 32-bit Flash player library from the adobe-flashplugin package (which is retrieved from http://archive.canonical.com/) and configures itself as default for Internet browsers. Additionally, it installs a 32-bit compatibility layer for 64-bit systems.

Conclusion

There is no change in the installed Flash player for 32-bit systems. For 64-bit systems, flashplugin-installer installs the 32-bit version of Flash and a related compatibility library which may be slower and less stable. I would recommend using the native 64-bit library instead (adobe-flashplugin).

Analysis

adobe-flashplugin was found in http://archive.canonical.com/pool/partner/a/adobe-flashplugin/?C=M;O=D (I haven't enabled the partner repository):

wget http://archive.canonical.com/pool/partner/a/adobe-flashplugin/adobe-flashplugin_10.3.181.26-0natty1_i386.deb

flashplugin-installer can be downloaded using apt-get download flashplugin-installer. For comparison, I downloaded the 32-bit package from http://packages.ubuntu.com/natty/i386/flashplugin-installer/download.

Programs used:

• dpkg-deb --control package_version.deb target-dir - extracts the control files (e.g. post-installation scripts) to directory target-dir
• dpkg -x package_version.deb target-dir - extracts the contents of the package to target-dir
• dpkg --contents package_version.deb - shows the contents of the package
• diff -Nur one two - compare directories one and two The postinst scripts were the most interesting as it makes the only difference between the packages.