As you explore your blog's dashboard, you've probably noticed the option to make "pages." If you're new to blogging, I feel it's important to understand the difference between a "post" and a "page" and what they can each be used for.
A blog by nature is not a static site. In other words, it's designed to constantly change have fresh content. When you open up any blog the first thing you come across is the text column on the home page. The blog home page is what features your blog posts. Usually the posts are displayed chronologically with the newest post being at the very top.
Which leads us to blog pages. All blogs have one default page: the home page. But you do have the option to add more pages. A "page" is static content. So a good example of a page you might want to have is an "about this blog" page. If you add an "about" page, it will add a permanent tab for people to click on your blog.
Pages are an extremely useful tool. Having pages such as an "about" will allow any new visitors to instantly see a summary of what you generally blog about and why. This helps to reduce confusion if your home page happens a few posts up that are seemingly unconnected.
Pages are also a good way to answer questions you are frequently asked. For example, if you run a book review blog, the submission guidelines would be a really good page to have. That way you don't have to tell every person that emails you what they are.
While pages are extremely useful, I recommend being extremely selective when adding them. I've seen blogs with 10 or more pages to click on and, personally, I find this to be a bit overwhelming. Most of the focus should be on the posts on your home page. The pages are just there as a tool.