The difference between Pages and Posts can be found here.
Please watch this basic tutorial on how to create and publish a new post
Posts are the most essential items for creating wonderful blogs to share with your viewers. Generally, posts created in WordPress will allow viewers to comment on any post the user puts up. It will automatically be turned on when you first create a new post and you can easily learn to turn off comments by going here.
If a blog is already setup in the customization menu, then each new post that is published will directly be posted to the blog. The posts are automatically archived and ordered in reverse chronological order.
Categories & Tags
Organizing your posts is easiest by using tags and categories. Using the categories option allows you to organize different posts into specific categories.
Tags also help organize posts and provide searchable keywords within your site.
For more clarification, please watch the videos below about categories and tags.
Note: If using featured content customization for the “Twenty-Fourteen” theme, the tag name should be added here for this post to be featured.