Any text containing more than a few lines (or sometimes even more) should exist inside of a paragraph tag <p>. This tag is reserved specifically for blocks of text, such as those you would expect to find inside your favorite novel.
<html> <head> <title>My Web Page!</title> </head> <body> <p>Avoid losing floppy disks with important school...</p> <p>For instance, let's say you had a HUGE school...</p> </body> </html>
HTML has heading tags which can be used as headers or subheaders. By placing text inside of an <h1> heading tag, for example, the text displays bold and the size of the text increases to a 24pt font size. Heading tags are numbered 1 through 6, and they change size depending on which tag you choose, with 1 being the largest font size at 24pt, and 6 being the smallest font size at 8pt.
<body> <h1>Headings</h1> <h2>are</h2> <h3>great</h3> <h4>for</h4> <h5>titles</h5> <h6>and subtitles</h6> </body>
Reference:
http://www.tizag.com/htmlT/htmltext.php