HTML tags are used to mark-up HTML elements.
HTML tags are surrounded by the two characters < and >.
The surrounding characters are called angle brackets.
HTML tags normally come in pairs like <b> and </b>.
The first tag in a pair is the start tag, the second tag is the end tag.
The text between the start and end tags is the element content.
HTML tags are not case sensitive, <b> means the same as <B>.