Help:Page History

All of the editable pages on UESPWiki have an associated page history, which consists of the old versions of the wikitext, as well as a record of the date and time (in UTC) of every edit, the username or IP address of the user who made it, and their edit summary. This may also be referred to as the revision history or edit history. To access the page history, click the "history" tab at the top of the page. 

Using a history page
On a history page:
All past changes to the page in question are listed in reverse-chronological order. 
To view a specific version, click a date.
To compare an old version with the current version, click cur.
To compare a version with its predecessor, click prev.
To compare two specific versions, tick the left-column radio button of the older version and the right-column radio button of the newer version, and then click the "Compare selected versions" button.
Minor edits are denoted as m (bot edits–b–are not distinguishable within the page history).

Below is a detailed example of a page history using the default skin:

thumb|1000px|left|An example of a page's history.
 
Edits are shown from newest to oldest. Each edit takes up one line which shows the time & date, the contributor's name or IP and the edit summary, as well as other diagnostic information.
Let's look at some of the functions of this page:
# This is the tab you click to access the history page.
# The name of the article.
# These links take you to the most recent edits (Latest), oldest edits (Earliest) or the next or previous page of edits (Next n / Previous n). Note that the black text in parentheses will become links, when applicable.  The blue numbers list the number of edits displayed on a page - 20, 50, 100, 250 or 500. A higher number increases the length of a page but reduces the number of pages The number you select replaces n in the links to the previous or next pages e.g. (Next 100 / Previous 100).
# (cur) takes you to a diff page, showing the difference between that edit and the current version. The current revision appears below the changes, so you can see how the page is now rendered.  (last) takes you to a diff page showing the changes between that edit and the previous version. The most recent version (the one on the same line as the "last" you clicked on) appears below the changes, so you can see how the page was rendered.
# The two columns of radio button can be used to select any two versions on the page. Lets say you want to compare the versions corresponding to numbers 7 & 9 on the image. First, click the left radio button next to number 9. The right column of buttons will then fill as far as number 9. Then click the right button next to number 7. Finally click Compare selected versions. This takes you to a diff page showing the changes between the two versions. The most recent version (in this case number 7) appears below the changes, so you can see how the page was rendered.
# This gives the time and date of the edit, expressed in local time according to the preference setting. The date and time link to the version of that day and time. Thus the  first line links to the version that was current at the time of loading this revision history, and therefore the result may differ from that of following the link on the page margin to the current version. Even if the page has not changed in the meantime, the info appears. The username or IP of the contributor also appears here.
# This is the edit summary. It is the text the user wrote in the edit summary box (below the edit box).   Also, this edit summary begins with an arrow link and grey text. This means the user has only edited a section of the page (named in the grey text). This text is automatically added when you edit a section. A standard edit summary can be added by the user. This appears in black text.
# m stands for minor edit. 
# This is the undo button. Click it to revert that edit (however, if edits to the same line of text within the article were edited after the edit you wish to undo, you will be unable to undo it).
# Other actions also appear in the edit summary, such as moves and protections.

It is possible to restore an old version of a page by following the link to that version, clicking "edit" and then saving. This should be done with caution, as it means that all changes made to the page since the time of that version will be lost.

Moved and deleted pages
When a page is moved (renamed), the entire edit history of the article, before and after the move, is shown. The old title becomes a redirect and loses its edit history. 

If instead of a move, the entire content was cut and pasted into a new substitute article, the page history gets spread across two articles. The histories can be merged in this case.

When two pages are merged, typically one becomes a redirect. In this case the revision history of the redirect is kept.

When a page is deleted, its revision history remains in the database and can be retrieved by an administrator, who can also undelete the page (see ).

Archiving
Archiving talk page text in separate pages is superior to using the page history as sole archive:
What links here works for archive pages, but not for old revisions.
Texts in archive pages can be found by search engines. For content which is only in a revision history the possibilities are limited. 
Archive pages can be organized and titled afterwards in a suitable way, while e.g. edit summaries cannot be supplied afterward. However, an index of old versions of a page, with links to them, could be prepared.