Post settings

The default maximum number of posts to display per page on overview pages such as the main page. The maximum number of characters used in the trimmed version of a post. Drupal will use this setting to determine at which offset long posts should be trimmed.

The trimmed version of a post is typically used as a teaser when displaying the post on the main page, in XML feeds, etc. To disable teasers, set to 'Unlimited'. Note that this setting will only affect new or updated content and will not affect existing teasers.

Also whether previewing a post is optional or required. This setting is across all content node types.