revision:
The <body> tag defines the document's body. The <body> element contains all the contents of an HTML document, such as headings, paragraphs, images, hyperlinks, tables, lists, etc. There can only be one <body> element in an HTML document. The <body> element contains the entire content of a webpage. It must be the second element inside of the parent <html> element, following only the <head> element.
onload : function call on page loading.
onunload : function call when user leaves the page.
onfocus : function call when document receives focus by user.
onblur : function call when document loses focus by user.
<body> . . . </body>
Codes:
<body> <h1>This is a heading</h1> <p>This is a paragraph.</p> </body>