In this post I'll be running you through all the steps you need to get you set up with a local server environment running with a copy of WordPress so you can play about with the code without worrying about who's looking at it or if you break it.
Taking a look at Wordpress as a viable option for non-blogging web sites, the alternatives available and resources for getting started.
If you're seeing this in your Wordpress application, it's a WP_Error to warn you that you don't have the appropriate extensions installed on your server or local machine to make an external HTTP request. It's common to see this on local server installations using software like WAMP or XAMPP that may not have these extensions on by default. There are various plugins that you might require this functionality, e.g. to connect to the Twitter API. This short post explains how to enable the cURL extension to resolve the issue.