This article will show how to install Flash Player on Ubuntu amd64 (64bit)
First of all, and to see if you have installed Ubuntu 64bit or 32bit Ubuntu, run in a terminal:
The terminal will respond: x86_64 (meaning it is 64bit) or i686 (then it is 32bit)
The flash version that is installed by default in the system is from Medibuntu repositories for Ubuntu amd64. It’s the same that is installed with the “ubuntu-restricted-extras” metapackage, but it is actually a 32-bit version, which is more stable. These instructions are for those who want the 64-bit version.
There are several ways to install 64bits flash and most of them will be discussed here.