I’m posting merely to show a post. A post can be anything, words, pictures, embedded videos. In a standard blog style wordpress setup, posts are quickly added and automatically move the newest to the top of the page.
I don’t normally use the standard wordpress blog setup, but some people really like to use wordpress as a blog, or a way to share stuff with their family or friends, so having the default 5 or 10 posts on a page, with the newest posts showing on the front page, is great for them.
Personally, and professionally, I like to use wordpress to show a static front page and put my posts in a different location. More on that in another post. Or maybe I should make that a static page. Yeah, a wordpress page for that.