[DC LoCo] OS on USB Stick

[Marti Martinson]

I am obviously NOT using the correct words in my google query.

My question is this: "Can an Ubuntu OS on a USB stick be updated (for
apps and packages) and/or upgraded (for releases) or not?"

I am curious because my everyday Ubuntu box was purchased from madtux
(when they were still in business) and they had something called a
LivePC which had no hard drive and no CD/DVD - only a USB. They
indicated that THEY could send you back an updated stick; I seem to
recall they only had Knoppix.

I have been seeing sites sell GNU/Linux distros on USBs, some up to
32GB. Since most LiveCDs are like 600-700MB, I am just curious.....

Thank you.

Marti