Headings

Heading gives appropriate weightage to the particular section. In HTML there are 6 levels of heading tags available. They can be used as <h1>, <h2>, <h3>, <h4>, <h5>, and <h6>.  Heading tags are paired tags, means we need to close tag, for example if we  initiated it with <h1> then we need to close it by </h1> at end. 

Heading tags also plays an important role in SEO (Search Engine Optimization). The most important heading is defined by <h1> and  <h6> tag represents the least important heading.   It is not recommended to use a heading tag for just increasing font size. Tags must be applied based on the importance of that headings.  

Also, note that the browser will automatically add linebreak before and after heading tag so no need to add manually.