If you've installed Ubuntu in the past, you might notice that, unlike its predecessors up to 12.04, Ubuntu 15.04 does not fit on one CD. As of 12.10 onwards, developers also improved the installer, which now provides full encryption and Logical Volume Manager (LVM). The step in 13.10 that allowed access to or set up of an UbuntuOne account was removed in 14.04. Other than these updates, not much has changed with the Ubuntu installation process.
Installing Ubuntu 15.04 on your computer or virtual machine can be done in several ways. Although Ubuntu is geared toward novice Linux users, installing the system is different from a Windows installation. We'll explain your options and walk you through the steps.
If you're running Ubuntu 14.10, you can update to version 15.04 directly. However, if you're upgrading from a version of Ubuntu earlier than 14.10, you will have to update in steps to 14.10 first and then to 15.04.
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