HTML generally has 2 parts an on code and an off code, which contain the text to be define. Few tags do not require an off code.
tag name> …..here code…… /tag name>
The most important thing to keep in mind about HTML is that its purpose is not specify the exact formatting or layout of a web page, but rather to define and specify the specific elements that make up a page such as the body of the text, heading, paragraphs, line breaks, text elements and so on. You can use HTML to define the composition of web page, not the appearance.