Writing posts is more or less similar to writing pages: you can define a Post Title, and write the Post Content just as regular pages. Clicking on the Post Options button in the top-right corner reveals some extra options which are Slug/URL, Tags, Publication date and the ability to make a post Private. A page slug is a user- and SEO-friendly short text used in the post URL. In the Tags field you can enter whatever keywords you see fit, as long as they are single words and seperated by commas. The publication date speaks for itself and making a post private prevents it from being displayed on the front-end part of your website.