The operating environment of this tutorial: Windows 7 system, HTML5 version, Dell G3 computer.
htmlUnpaired tags
## : A simple line break can be inserted. The
tag is an empty tag (meaning it has no closing tag, so this is an error: ). In XHTML, place the closing tag within the opening tag, i.e. .
: Defines topic changes in HTML pages (such as topic shifts) and displays them as a horizontal line.
: Defines the area inside the image map (image map refers to an image with a clickable area).
: Specifies the default address or default target for all links on the page.
: Define images in HTML pages.
: Specifies an input field in which the user can enter data.
: Defines the relationship between the document and external resources. The most common use is to link style sheets.
: Provides metadata for the HTML document. The metadata will not be displayed on the client, but will be parsed by the browser. The META element is usually used to specify the description, keywords, last modification time of the file, author and other metadata of the web page. Metadata can be called using browsers (how content is displayed or pages are reloaded), search engines (keywords), or other web services.
: Defines the default color, size, and font for all text in the document.
: Allows you to specify run-time settings for the object inserted into the XHTML document, that is, this tag can be the
: Specifies the column attributes of each column inside the
element. By using the
tag, you can apply a style to an entire column without having to repeat the style for each cell or row.
: Define a specific window (frame) in the frameset. Each frame in the frameset can set different properties, such as border, scrolling, noresize, etc.
Specifies the key pair generator field to use for the form.
: Defines media resources for media elements such as
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