I found this article by Kristi Hines explaining the difference between a Blog and a Static Website.
Static websites consist of content presented on static pages. Static websites owners rarely update their pages, whereas a blog owner updates their website with new blog posts on a regular basis.
Key elements that identify a blog post from a static page include a publishing date, author reference, categories, and tags within a byline. While not all blog posts have all of those byline elements, static website pages do not have any of these elements.
From a visitor perspective, the content on a static website will not change dramatically from one visit to the next. The content on a blog, however, has the potential to offer something new each day, week, or month, depending on the blog owner’s publishing schedule.