‘applyBodyTag’ has Boolean attribute type. A Boolean value that specifies whether or not Visualforce should automatically add a <body> tag to the generated HTML output. Set to false to disable adding the <body> tag to the response, for example, when the <body> tag is statically set in your markup. If not specified, this value defaults to the value of the applyHtmlTag attribute if it’s set, or true, if applyHtmlTag isn’t set.