Updated 2009-07-23 05:03
In a nutshell...Versions of a page usually fall into one of three categories:
Versions begin as Newly Edited. They are usually promoted to Edited after 3 days. If they are good, they can be promoted to Main.
Promotion from Newly Edited to EditedYou create a Newly Edited version when you create a page or edit an existing page. After 3 days it will be promoted to be an Edited version, presuming the page wasn't identified as spam or archived (see Spam or Archived below). When you edit the version again, the 3-day count starts over.
Promotion from Edited to MainAn Edited version can optionally be promoted to the Main version after it has been suggested (see Suggesting as Main below). Once a version has been promoted to main, if you edit it again the main version remains in place while a new newly edited version is created. You can then, of course, suggest it should replace the main version.
More detail about versions
Main - These are the most prominent versions. There is only one main version of each page (whereas there can be several Newly Edited and Edited versions of a page). Main versions are meant for everyone to see and contribute to.
Edited - Visible by everyone.
Newly Edited - Visible by everyone but hidden from search engines (since new edits could be spam -promotional or offensive content). However, they are publicly viewable right away and you can send links to them to friends.
Suggesting as MainIf you think a version should become the main version you can suggest it. To do so, go to the version and click "page" (on the right) and then click "suggest as main". This will cause it to be reviewed, and usually made the main page within a few days.
Which pages should be suggestedIf you think your version is of general interest and want to let anyone contribute to it, consider suggesting it as main. If you think it is not of general interest or you want to maintain control of your version then don't suggest it as main.
There's only one main versionThere's only one main version of any page, so when a version gets promoted to main it replaces the current main version (if one exists). To replace an existing main version, a version must be an improvement to it. It normally shouldn't remove anything important from the current main version (unless it has been moved to another page). Also, there shouldn't be redundancy with other main versions (although displaying the same information in different ways is acceptable).
How do I improve my page so it can become a main version?Main versions should have consise appropriate names. Consider changing the name of your version to better reflect what is on it. For example, if you add a table about egg rolls to the Chinese page your version won't likely get promoted to main. However, if you create a Chinese Food page and put your egg rolls table there, it will likely get promoted to main. To help people find your page, you'll probably want to create a link from the Chinese page to your Chinese Food page (see Linking Quickstart). Or, if there's already a Chinese Food page with a lot of content, consider making an Egg Rolls page.
Pages with many small tables with appropriate headings are easier to learn, and will be more likely to be promoted as main. (Remember you can always learn multiple tables at once by using the "combine" link.)
Adding descriptive paragraphs to your page can increase their usability as well (such as with Piano and Commonly Confused Pronouns) and can increase their chances of getting promoted.
Merging in the good parts from multiple versionsSee Sharing Quickstart for information about merging parts of another version into your version (you may wish to do this before suggesting a page as the main version).
Spam or archivedUsers can suggest that a version is spam or should be archived. This is done by going to the version and clicking "page" (on the right) and then clicking "spam" or "archive".
Spam - Promotional or offensive content. Help us identify spam so we can delete it.
Archived - Versions not likely to be useful to users in general, but aren't bad enough to be deleted.