1.& lth 1 & gt； & lt/h 1 & gt； ，& lth2 & gt& lt/H2 & gt； ，& lth3 & gt& lt/H3 & gt； ....& lth6 & gt& lt/h6 & gt； They are usually called title tags, h 1 stands for the first-level title, h2 stands for the second-level title, h3 stands for the third-level title ... They are block-level tags without default attributes and double tags. However, they all have default styles, with upper margin and lower margin, and their values are different. There are different font sizes and font thicknesses.
2.& ltHR/>； He is a dividing line label, a block label, and a single label. He has the default style values, he has the top margin and bottom margin values of 8px, and there is a border.
3.& ltp & gt& lt/p & gt； The default style values of paragraph tags, block-level tags and double tags (note that block-level tags cannot be nested in P tags) are margin-top and margin-bottom, both of which are 16px.
4.& ltol & gt& lt Li>& lt/ Li>& lt/ol & gt；; Ordered list labels, ol and li exist in pairs. He is a double standard, a combination standard and a block standard. Ol ordered list area, Li list items. The default style values of Ol are 16px margin and 40px left padding. ?
5.& ltul & gt& lt Li>& lt/ Li>& lt/ul & gt；; Unordered list labels, ul and li exist in pairs. He is a double standard, a combination standard and a block standard. Ul unordered list area, li list items. The default style values of Ul are 16px margin and 40px left padding.
6.& ltdl & gt& ltdt & gt& lt/dt & gt； & ltdd & gt& lt/DD & gt； & lt/dl & gt； Dictionary label, dl label is double label, block label. The default style value of Dl is 16px margin.
Dd also has a default style. Its left margin is 40 pixels.
7.& ltA href = "# # "(jump address is required and cannot be empty) Target =" jump mode _ blank new window opens "> < /a & gt； He is a line label, double label.
It has four pseudo-class attributes, which are: a:link (link status is not browsed), a:visited (active mouse click not released), a:hover (hovering mouse over link), and a:visited (visited link). Different periods have different default styles.
8.& ltImg src= "(picture address)" alt= "(information provided when the picture fails to load)" > It is a picture label, and a single label, such as special, can be set in size although it is at the line level. But he doesn't belong to the line block label either. Supporting width and height attributes does not require adding units. Generally, only one width and height are set.
9.& ltstrong & gt& lt/strong & gt； Bold label, double label, line-level label. Generally used to emphasize. Its default style is font weight.
10.& ltem & gt& lt/em & gt； Italic label, double label, line-level label. Generally used to emphasize. Its default style is the font style.
1 1 & lt； big & gt& lt/big & gt； ; & ltsmall & gt& lt/small & gt； Double label, line label. Generally used to emphasize. Its default style is font size. Note that its font size has changed relative to the parent font size.
12.& ltsub & gt& lt/sub & gt； ，& ltsup & gt& lt/sup & gt； ，& ltdel & gt& lt/del & gt； Indicates text subscript, text superscript and deleted text respectively.