You may think, what is RSS and how to add RSS Feed in wordpress and what will you get from it. RSS stands for "Rich Site Summary" or "Really Simple Syndication", said for you to understand me is a way to offer your updated content to people who want to be aware of your posts without having to continuously enter your website. ¡Be careful, this has nothing to do with email, every time you post something DOES NOT automatically reach subscribers RSS but it is they who decide when they open their reader and see your updates.
Example: You post your wonderful post tonight at 23:30 after a hard day, at that time I am already happily asleep and the next morning, When I wake up at 6 in the morning and open my reader, there I have a notice telling me that you have published something new and giving me the opportunity to read it. ¿Do you follow me?

What do you have to do to have it?

Nothing absolutely. WordPress takes care of everything. By default, create an enriched text file ( that is, nice post text ) that is hidden unless someone searches for it. This file is called feed. And where is my feed? Well, if you haven't touched anything, you should find it in yourdomain.com/feed come on adding /feed after your URL. I already warn you, restless soul, that if you enter that address all you are going to see is a horrible page, full of code but that, luckily, the programs that read the feed, know how to interpret.

Setting up our WordPress widgets

We are going to start from our Desk, in the menu "Aparience" and "Widgets. There we will find precisely the widget page. On the left we will see the available ones and the many elements that we can add to our widgets, while on the right we will see the areas available for it. By dragging and dropping we can configure our widgets quickly and easily. Although depending on the topic we are using, the areas available for widgets that we will have may be different, We are going to do this example in a very common area for most topics. This is the sidebar or sidebar, which in turn depending on the case, will have more or less areas available.

Show an RSS feed in the sidebar widget

On the left side of our widget configuration screen, where the items are available to include, we have one that is precisely called "RSS. On the right, as we said depending on the topic, we will have an area called “Sidebar”. What we will simply do is click on the RSS on the left, drag it and drop it into the Sidebar widget. Now we must configure the widget, for that we will specify:

• The URL of the feed to display ( generally at the end it has the extension "/ feed" )
• Title what we will give to the widget
• Number of entries of the feed that we will show in our widget
• We choose if we are going to show the content, author and date. We can show some, all or none of them.

To finish we save the changes. You can customize your rss feed even can add new rss feed using WP RSS Aggregator. You can diplay external rss feed in your site in some ways.