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Will there be data loss for upgrade?
Can we upgrade a previous version of ubuntu to the latest version without losing data ? (For example, will I be able to upgrade the 10.10 version to 11.04, which is due to be released in April of 2011?) I mean, there is a new version coming out every 6 months, so it will be convenient if we are able to upgrade without losing on the data .
Yes. Upgrades do not erase your settings/data. You can run the command sudo do-release-upgrade in terminal to check for available upgrades. Run do-release-upgrade -h to see options, such as how to upgrade early (prior to release).
Also, if you know what you're doing, you can partition your hard drive to place your /home on its own partition.1 This enables you to wipe your install if anything goes wrong and reinstall without losing your settings/data.
Just use the update manager. It will report if the new version is available. It won't destroy your data.
You can safely update from within Ubuntu using the Update Manager though there is other options available, the following link to the Ubuntu website should provide you with enough info (though it details 10.04 to 10.10 it will be the same for 10.10 to 11.04).
