I looked it up in Wikipedia, and there is only one line there. Anyone have a more detailed description for it? Ubuntu releases their OS with this notation, but I was unable to find a detailed description over what it means/includes. I've already read the Ubuntu notation but need a more general description, not how Ubuntu has implemented it.
I don't believe "LTS" has any general definition, so any answer will have to focus on what Ubuntu mean by "Long Term Support"
But, just to add xsl's answer, using the LTS versions on servers allows you to have some confidence you can deploy servers which are going to be regularly patched but will not need upgrades of the entire OS.
Also, non-LTS Ubuntu upgrades need to be carried out in sequence, i.e. to go from 7.10 to 8.10, you would first need to upgrade to 8.04
With the LTS releases, there is a clear upgrade path from one LTS release to the next, i.e. from 6.06 you can go straight to 8.04