Differences between "updates," "upgrade," and "version-upgrade"

Question

The upgrade documentation at https://drupal.org/upgrade states that an upgrade consists of changing the major version while an update is changing the minor version of Drupal.

Excerpt:

What's the difference? Major versions (upgrade) versus Minor versions (update)

Before you start updating or upgrading your Drupal installation it is important that you know the difference between a major and a minor version release.

We know that applying updates is part of the routine maintenance tasks, whereas an upgrade is a task of a different scale, a project that presumably involves adjusting code, design, modules, etc.

Yet when tagging a question with upgrade, it gets renamed automatically to updates as they are the same thing. I assume one is set as a synonym of the other.
version-upgrade is also suggested, and that would theoretically be fine, except that almost nobody seems to use it (3 questions only).

When searching for questions on upgrades, this confusion between tags doesn't help because questions on upgrading like Upgrading a site from Drupal 6 to 7 using Drush
get tagged the same as questions on updating like How to get update to check Feature Server.

Wouldn't it be better if they were not synonyms and their descriptions were aligned with Drupal.org's documentation?

Answer 1

I have fixed the tags. Now there are two tags:

• updates
• upgrades

Upgrading a module/site is different than updating it; the first is generally a more complex operation, and often the more problematic one.
Users who answer updates questions could not be prepared to answer upgrades questions; users who are checking if somebody had their same upgrading problem (and asked a question on Drupal Answers) would find questions about updating. For this reason, I re-tagged the questions that should use upgrades.

I guess that at the time the synonym was set, the two tags were used as if they were synonyms; in fact I found at least a question whose title speaks of updating, but whose text speaks of upgrading.
It seems also that migration gets sometimes used instead of upgrades, when the question doesn't make clear the OP migrated the site from a domain to another), but that is a different story.

I replaced version-upgrade with upgrades, since version upgrade doesn't convey any specific meaning.

Now we just need volunteers who write the tag wikis for those tags.