Hello hamlethub ,
To Cache Settings
Cache Settings – set it to On – Progressive Caching if you’d like maximum caching and fastest Joomla. Set it to On – Conservative if you’d like to disable modules caching. In any case there is cache time in minutes. During this time changes may not appear because cached copies will be served to the viewers.
It depends on your site.
For example if you use they random image module the page will be cached
and you will not see a different image until the cache expires.
Depends on your Cache Lifetime setting.
If you only update your site once a week, then why not set the Liftime really high?
Why make unnessecary database calls. You could allways clean your cache if needed.
(Tools -> Clean Cache)
Cache Settings In Global Configuration:-
* Cache. This setting sets whether site caching is enabled or not. When enabled, it keeps a local copy of the content on the server to speed up accessing and lessen stress on the database. The default setting is No.
* Cache Time. This setting sets the maximum length of time (in minutes) for a cache file to be stored before it is refreshed. The default setting is 15 minutes.
* Cache Handler. This setting sets how the cache operates. There is only one caching mechanism which is file-based.