Let me answer this question in two parts.
- Definition of Blogger Feed Files
Blogger formats all posts content and comments content inside a file called XML which has two types
Atom Feed located at your-Domain.com/feeds/posts/default
RSS FEED located at your-Domain.com/feeds/posts/default?alt=rss
Both these files give information of your entire blog to third-party services like Search Engines, Feed Readers and makes it possible to build widgets using [JSON API]. Using these files, readers subscribe to your blog and robots are informed whenever a new update is made on your blog. It’s simply the index of all data about your blog in plain text. All those fancy magazine Blogger templates that you see these days could never be developed if these files were not present.
Feed files shares info such as post title, date, time, author name, comments count, comments posted, post summary, thumbnail image used and so on.
- Show Full Feed or Half
Let me first explain each option in detail:
- Select Full to syndicate the entire contents of your post.
- Select Until Jump Break to show all post content before your ‘Read More Link’.
- Select Short to syndicate approximately the first 400 characters.
- If you select None, your blog will not be syndicated and its content will not be indexed by Google Blog Search.
The best option to choose is always Full because it shows full content of your post and doesn’t just show half summary above jump break. This option also helps to List posts by Label using the JSON API.
There is no big difference between Short and Until Jump Break. If you choose this option, you will not be able to effectively create widgets using the json api. Which means you can not display posts by label on your homepage or create widgets that uses the JSON script to call data from your Feed file. It may surely work but the AJAX call is often slow with these options,
- People normally choose this option because they want Feedburner to only show post summary to email subscribers so that they may read the full post on the blog and not through email. They do this to push traffic to their homepage from their email list. It is surely a good strategy but do this if your blog has no Magazine style structure. At MBT we have chosen Until Jump Break option because we don’t use JSON API here.
Never Choose None because it will simply make your blog disappear from search and online blog directories.
The Custom option lets you set feed summary length for comments. You can choose it if you are developing widgets using comment Feed.
Hope this helps! Peace buddy