Layout Tags (header, footer, nav, aside)

          An <article> element describes a self-contained composition in a page, application, document, or site intended to be independently reusable or distributable (e.g. a newspaper or magazine article, a user- submitted comment, a blog entry, a forum post etc.).

          The given markup below displays how the <article> element could be used: 

<article>
   <h1>This is article heading</h1>
   <p>
   Hello world! Hello world! Hello world!
   Hello world! Hello world! Hello world!
  Hello world! Hello world! Hello world!
   </p>
</article>

          Sometimes <section> and <article> are used together and sometimes, on nested <article> elements. There are no rules dictating their nesting.