Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things
Why its hard to update
Upgrading Breezy to Dapper via apt-get can be problematic. If you just installed Breezy then why not just burn a Dapper CD and install it. I had all sorts of problems considering the upgrade from Breezy to Dapper. There were issues with the X server that had to be configured, applications launched slower, and many other problems. Upgrading can also place holes in your OS so the best option is probably to just install Dapper fresh.
Upgrading Ubuntu Linux is just as easy as installing a new package. Simply run these commands, and your system will be updated:
sudo sed ’s/hoary/dapper/g’ /etc/apt/sources.list > /etc/apt/tmp && mv /etc/apt/tmp /etc/apt/sources.list sudo apt-get update sudo apt-get upgrade sudo apt-get -y dist-upgrade