On the internet there are many different types of written content.
An Article is traditionally a long non-fiction piece, describing something in detail. It is usually timeless and can exist as standalone content.
A Blog is a collection of dated posts that are often short and to the point. While still being factual, they generally lean towards being a platform for the blog author to express their opinion.
A Press Release is a very concise statement aimed at the general public to announce something newsworthy and written in order to highlight an important event, program or piece of information.