§Rebuilding Files.
Normally, Pivot rebuilds the frontpage when you post a new entry, or when users leave comments. Sometimes you just don't want to wait for that. Or maybe the backend database of Pivot is corrupted somehow. That's where rebuilding comes in.
§Rebuild the Frontpage(s)
As said above, Pivot rebuilds the frontpage when you post a new entry, or when users leave comments. But what if you made some changes to the frontpage template? You'd want to see that immediately.
When you choose this option, Pivot rebuilds the frontpage, last archives and RSS files for each of the weblogs you have. Basically, if things don't look the way as intended, rebuild the frontpage, and chances are that everything looks the way as it should be again.
§Rebuild All Files
Rebuild all files if you want not only the pages mentioned above to change, but also all the archives Pivot generates. Usually you'll do this when you have made major changes to your archivepage template. By rebuilding all the files the looks of your site remain the same for all of its files, old archives included.
An interesting side-effect here is that, if you choose not to rebuild all files, visitors can browse the old archives and see what your site looked like before you revamped it. If you are the one that produces a new layout every season, you should probably leave this option alone!
§Rebuild the Index
During normal operation, it shouldn't ever be necessary to rebuild the index. But strange things happen to servers sometimes, and in some of these cases, the underlying database system of Pivot can get corrupted. This can be fixed by rebuilding the index.
§Rebuild the Search Index
Rebuilding the search index should only be needed on two occasions: The first is if you set Autoupdate search index to no in the Configuration screen for some reason. You then have to update the search index manually from time to time.
The other occasion is that, when you started your weblog, you didn't include the search option in the templates, and want to add it later on. Old entries should be indexed before they can be found. Remember that if you add the search option later on, you'll also have to check the Autoupdate search index in the Configuration screen to see if it's set to yes!