Download upgrade?

[MiyamotoSamurai]

I have ubuntu like 8.0 or something like that, and i upgrade now to 9.10

The upgrade is like 600 mb. I have this 8.0 ubuntu on a cd. Lets say i need to format my pc and lose everything, and instal new. Then i would have to instal ubuntu 8.0 from cd and then upgrade again. Is there a way to download the upgrade as there is exe in windows, what should i do? So that i dont have to download it again if i need to reinstal. To download for ubuntu 9.10 and download that?

thanks

[James.H]

Can't you just download it directly from the site and save it on a CD or USB?

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