11.11. HTML <head>

发布时间 :2024-02-22 23:00:05 UTC      

11.11.1. HTML <head> element

<head> element contains all the header tag elements. In <head> can insert scripts (scripts), style files (CSS), and various meta messages into the element.

The element labels that can be added to the header area are: <script> , <noscript> and <base>

11.11.2. HTML <title> element

<title> tags define the titles of different documents.

<title> is required in HTML/XHTML documents.

<title> elements:

  • Defines the title of the browser toolbar

  • The title displayed in the favorites when the web page is added to the favorites

  • The title displayed on the search engine results page

A simple HTML document:

Example

<!DOCTYPEhtml><html><head><metacharset="utf-8"><title>document title</title></head><body>document content......</body></html>

11.11.3. HTML < base > element

The <base> tag describes the basic link address / link destination and serves as the default link for all link tags in the HTML document:

<head>
<base href="http://www.runoob.com/images/" target="_blank">
</head>

11.11.5. HTML <style> element

<style> tag defines the style file reference address of the HTML document.

In <style> can also add styles directly to the element to render the HTML document:

<head>
<style type="text/css">
body {background-color:yellow}
p {color:blue}
</style>
</head>

11.11.6. HTML < meta > element

The meta tag describes some basic metadata.

<meta> tag provides metadata. The metadata is not displayed on the page, but it will be parsed by the browser.

The META element is often used to specify the description of the web page, keywords, last modification time of the file, author, and other metadata.

Metadata can be used in browsers (how to display content or reload pages), search engines (keywords), or other Web services.

<meta> is generally placed in <head> region

11.11.7. <meta> label-use instance

Define keywords for search engines:

<meta name="keywords" content="HTML, CSS, XML, XHTML, JavaScript">

Define the description for the web page:

<meta name="description" content="Free Web&Programming Tutorial">

Define the author of the page:

<meta name="author" content="Runoob">

Refresh the current page every 30 seconds:

<meta http-equiv="refresh" content="30">

11.11.8. HTML <script> element

<script> tags are used to load script files, such as JavaScript.

<script> elements are described in detail in later chapters.

11.11.9. HTML head element

Label

Description

< head >

Defines the information of the document

< title >

Defines the title of the document

< base >

Defines the default link address for the page link label

< link >

Defines the relationship between a document and external resources

< meta >

Defines the metadata in the HTML document

< script >

Defines the script file for the client

< style >

Defines the style file for the HTML document

Principles, Technologies, and Methods of Geographic Information Systems  102

In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress.