Upgrade to Ubuntu 10.04 : From Ubuntu 9.10 or 8.04

I will explain how to upgrade from Ubuntu 9.10 or 8.04 to Ubuntu 10.04
Before you begin upgrading:Make sure that your system has all old updates, and to do this:
sudo apt-get updatesudo apt-get upgrade
Upgrade from Ubuntu 9.10:
Go to : System / Administration / Update Manager , and click on Check and wait until completion to get latest updates.Now if you have any developed new packages you have