Most RSS feeds are automatically generated by whatever blogging software or content management system is being used. If you have written your own application for doing this, you will need to generate your own feeds. This is fairly easy if your application is built around a database back end, because you can generate the feed by pulling the information straight from the database; however, if you do not use a database (like if you write static pages of HTML) you will need to create your feeds manually.
For database-based sites, there are basically two approaches to generating RSS feeds:
Create a "static" page by drawing the data from the database and writing into an XML file. This is the best approach if you have a heavy access load to handle.
Generate a "dynamic" page by drawing the data from the database and spitting it out upon request. If you go down this route, you may need to arrange for some sort of caching if the load becomes heavy.
I use the first option with my hand-rolled, PHP-based blogging application. I pull the information of the database, format it into valid RSS (also Atom) and then write it into a static file. This happens whenever I create a new blog entry, or update an existing one. You can see the resulting file here: http://jessey.net/blog/rss.xml View the source of the file to see how to correctly format a simple RSS feed.
-- si-blog --
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