When creating a new post on your WordPress website, you may notice that you have a variety of boxes, also known as “metaboxes”. These metaboxes offer customizable options for publishing your post, such as adding Tags to entry or selecting whether or not comments are allowed on your post.
Editor
The Editor is where you type the content of your post.
Publish
The publish meta box includes your Post Status, Post Visibility, and when your post was published. 
The Post Status shows whether a post is published or unpublished. 
- Published – The post has been published on your blog for all to see.
- Scheduled – When the post’s timestamp is set in the future for automatic publishing. See Schedule a Post for more information.
- Pending Review – The post has been submitted by a Contributor. It must be published by an Editor or Administrator before it is visible to blog readers.
- Draft – An unpublished post. The post will not be visible to readers until the post is published.
You can learn more about changing your Post Visibility, including password protecting a post, here. You can also schedule a post by following this guide.
Post Title and URL
The Title and URL of a post are related by default. When you initially enter the title of your post, the post slug (used in the permalink/URL) is automatically created.
The post slug is the part of the URL after the date in a post’s URL. When the default post slug is created, all letters will be converted to lowercase, spaces will be exchanged with dashes, and any special characters will be removed. You can modify the post slug by clicking the Edit button next to it. When you’re finished editing, click OK. After you are done making your changes don’t forget to click the Update button to update the post and save these changes. 
This is especially handy if, for example, your page title is very long, but you would like a URL that people can remember more easily. If your language uses a non-western character set, long post titles can break post slugs. To fix that, shorten the post slug to a single word.
Post Format
For themes that support post formats, you have the ability to select which format you’d like to use for each post. Learn more about formatting options here.
Tags and Categories
Tags and categories allow you to group your posts together. Learn more about adding categories and tags to your posts.
Featured Image
Some Themes use a Featured Image alongside the content. This could be a post thumbnail, or a header, or whatever the Theme designer has decided to implement. You can read more about Post Thumbnails on the WordPress Codex.
Discussion
The Discussion meta box is used to turn the discussion options on/off for the post. There are checkboxes for:
- Allow comments on this post
- Allow trackbacks and pingbacks on this post
If you want to set the defaults for these checkboxes, you can do so in your site’s Discussion Settings.
If you are editing a previously published post, the Discussion module would also show any comments for the post. 
Post Author
The Author meta box is used to change the author of a post. To change a post’s author, use the dropdown menu to select the new author and click Update or Publish to save the changes.
Excerpt
Some themes support using Excerpts, or summaries, of your post.
Trackbacks
Trackbacks are a way of letting other bloggers know when you’ve linked to their site.
Custom Fields
Custom Fields are a way of adding extra meta data to your posts. Some Themes may create their own Custom Fields to display different types of content. You can read more about Custom Fields in the Codex.
Troubleshooting
If you’re missing one of the meta boxes listed above on your New Post or Edit Post page, you may need to enable it in your Screen Options settings. This guide explains how to enable and disable the modules on your New Post page.