Calender
At this point you have only one post, and it is located on the main page. If you click on post title, then you will see a completely different page, revealing the contents of this post. Some designers do these pages differ from the principal.
Well, again, pay attention to layout and the difference between design elements. Another title? Smaller font? Bigger? In general, a different color? There is a sidebar? For example, the default theme on the single post page sidebar is removed. In general, we look and pay attention to all the difference.
Typically, positions are categorized, which allows you to store related publications together. Currently, you have only one category, but do not worry. Soon they will be much greater. Click on the category heading in the sidebar on the home page. Taken to a page that contains posts relating only to this category. Again, look at the layout and look for differences.
Same thing with the archive. Even one post is enough to see the general differences in design and layout of various pages and to understand the basic principles of operation.
All these differences are achieved by editing a few special files, called templates. Learn more about templates, you can see Introduction to Templates.