What is the difference between heading and paragraph?
As mentioned earlier the difference is that headings show layers which is used for search engines while paragraphs can be inside one heading to talk about a specific subtopic within a general topic. The paragraph though is not used as a type of layer like headings.
for human, only their apparence (styling) is different.
Heading : Which is written in <body> ... </body> tag where the visuals can be written as headings, paragraphs, ... in this tag headings can be written in <h1>..</h1> <h2>..</h2> <h3>..</h3> <h4>..<h4> <h5>..</h5> <h6>..</h6> in descending order of the sizes and now when we come to the Paragraph Paragraph : Which is also written in <body>...</body> tag in this we can write 'n' number of lines as a paragraph with in the <p>...</p> tag
headings is defined to show the document structure . but the paragraph are defined with the p tags