The composition and meaning of the URL

1.url-uniform Resource Locator
When you click a link in an HTML page, the corresponding <a> label points to an address on the World Wide Web.
A Uniform Resource Locator (URL) is used to locate documents (or other data) on the World Wide Web.

2.?

1) connection function: for example

Http://www.xxx.com/Show.asp?id=77&nameid=2905210001&page=1

2) Clear the cache: for example,

Http://www.xxxxx.com/index.html http://www.xxxxx.com/index.html?test123123

Two URLs open the same page, but this one has a question mark, indicating that the cached content is not called, but is considered a new address, re-read.

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Spacers for different parameters

Detailed

Transferred from: http://blog.csdn.net/dzhj11/article/details/9194999

A Uniform Resource Locator (URL) is an identifying method that is used to fully describe the address of web pages and other resources on the Internet.
Each Web page on the Internet has a unique name identifier, often referred to as a URL address, which can be a local disk or a computer on the LAN, and more sites on the Internet. Simply put, URLs are web addresses, commonly known as "URLs."
A URI scheme set that contains explicit instructions on how to access resources on the Internet.
URLs are uniform because they take the same basic syntax, regardless of which particular type of resource (Web page, newsgroup) is addressed, or which mechanism is used to obtain the resource.
For destination files on an Internet server or a World Wide Web server, you can use the Uniform Resource Locator (URL) address, which starts with "http://". The WEB server uses Hypertext Transfer Protocol (HTTP), a "behind the scenes" Internet Information Transfer Protocol. For example, http://www.microsoft.com/is the World Wide Web URL address for the Microsoft Web site.
The general format of the URL is (optional with square brackets []):
Protocol://hostname[:p ORT]/path/[;p arameters][?query] #fragment [edit this paragraph] format description: The composition of the URL
The URL consists of three parts: the protocol type, the hostname and path, and the file name. There are several main types of URLs that you can specify: HTTP, FTP, Gopher, Telnet, file, and so on.
1. Protocol (Protocol): Specifies the transport protocol used, and the following table lists the valid scheme names for the Protocol property. The most commonly used is the HTTP protocol, which is currently the most widely used protocol in www.
File resources are files on the local computer. Format file://
FTP accesses resources through FTP. Format ftp://
Gopher accesses the resource through the Gopher protocol.
HTTP accesses the resource over HTTP. Format/HTTP/
HTTPS accesses the resource through secure HTTPS. Format https://
The mailto resource is an e-mail address that is accessed through SMTP. Format mailto:
MMS plays the resource by supporting the MMS (streaming) protocol. (on behalf of software: Windows Media Player) format mms://
ED2K access to this resource through peer-to software that supports the ed2k (dedicated download link) protocol. (Representative software: Electric Donkey) format ed2k://
Flashget access to this resource through peer-to software that supports Flashget: (dedicated download link) protocol. (on behalf of the Software: Express) format flashget://
Thunder access to this resource through peer-to software that supports the Thunder (dedicated download link) protocol. (Representative software: Thunderbolt) format thunder://
News accesses the resource through NNTP.
Tencent by supporting Tencent (dedicated chat connection) protocol and user conversations. (on behalf of the software: QQ, TM) format tencent://message/?uin= number &site=&menu=yes
Msnim by supporting Msnim (dedicated chat connection) protocol and user conversations. (on behalf of software: MSN, WLM) format msnim:chat?contact= e-mail address
2. Hostname (hostname): Refers to the domain Name System (DNS) hostname or IP address of the server hosting the resource. Sometimes, you can also include the user name and password (format: Username:password) that you need to connect to the server before the host name.
3, port (port number): integer, optional, omit when using the default port of the scheme, the various transport protocols have a default port number, such as the default ports for HTTP 80. If omitted when entered, the default port number is used. Sometimes for security or other reasons, the port can be redefined on the server, that is, the non-standard port number, at this time, the URL can not omit the port number of this item.
4, Path: A string separated by 0 or more "/" symbols, typically used to represent a directory or file address on a host.
5.;p arameters (Parameters): This is an optional option for specifying special parameters.
6. Query: Optional, for dynamic Web pages (such as using CGI, ISAPI, php/jsp/asp/asp. NET and other technical Web pages) pass parameters, can have multiple parameters, separated by the "&" symbol, the name and value of each parameter is separated by the "=" symbol.
7, fragment, information fragment, string, used to specify the fragment in the network resource. For example, there are multiple noun interpretations in a Web page, and you can use fragment to navigate directly to a noun interpretation.
Note that Windows hosts do not differentiate between URL case, but Unix/linux hosts are case-sensitive. [edit this paragraph] The URL locator identifies the following list of services or files that are located and identified in the common URL:
http: File on the Web server.
File: Files on your own local system or on an anonymous server
ftp: File on the FTP server
Gopher: File on Gopher server
WAIS: File on WAIS server
News: The file is on a Usenet server
Telnet: Connect to a server that supports Telnet telnet
URL forwarding
The so-called URL forwarding, through the special settings of the server, will access your current domain name of the user to boot to another network address you specify. For example, URL forwarding allows users to automatically turn to a URL "http://www.123.com" that you specify when accessing http://www.abc.com, and the URL forwarding feature is a value-added service after the domain name registration provided by WAN network.
URL Development Background
URLs, also known as Web addresses, are the address of standard resources on the Internet. It was originally used by Tim Berners-Li Faming as the address of the World Wide Web. It has now been compiled by the World Wide Web Consortium as the Internet standard RFC1738. In the history of the Internet, the invention of the Uniform Resource Locator is a very basic step. The syntax for a Uniform Resource locator is generic and extensible, and it uses part of the ASCII code to represent the address of the Internet. The beginning of a uniform Resource locator typically marks the network protocol used by a computer network.
Related information
URI scheme set
Contains explicit instructions on how to access resources on the Internet.
URLs are uniform because they take the same basic syntax, regardless of which particular type of resource (Web page, newsgroup) is addressed, or which mechanism is used to obtain the resource. For destination files on an Internet server or a World Wide Web server, you can use the Uniform Resource Locator (URL) address, which starts with "http://". The Web server uses Hypertext Transfer Protocol (HTTP), a "behind the scenes" Internet Information Transfer Protocol. For example, http://www.microsoft.com/is the World Wide Web URL address for the Microsoft Web site.
Uniform Resource Locator and Uniform resource identifiers
A Uniform Resource Locator is a variant of the Uniform Resource marker. The Uniform Resource identifier determines a resource, and the Uniform Resource Locator not only determines a resource, but also indicates where it is. For example, the following Uniform Resource identifier determines the Internet Engineering Working Group RFC1738, but does not say where to find the information: urn:ietf:rfc:1738. The following Uniform Resource Locators identify each RFC1738 document, and also determine where these documents are found:
* Http://www.ietf.org/rfc/rfc1738.txt
* Http://www.w3.org/Addressing/rfc1738.txt
* http://rfc.sunsite.dk/rfc/rfc1738.html
Almost all of the Uniform Resource identifiers in history are Uniform Resource locators, so much of what is covered in this article is the same for both.
Uniform Resource Locator: The beginning of each Uniform Resource Locator is the system of the Uniform Resource Locator, followed by different parts of the system.
Daily use of Uniform Resource Locator
Hypertext Transfer Protocol Uniform Resource Locator The four basic elements that will get information from the Internet are included in a simple address:
1. Transfer Protocol;
2. Server;
3. Port number;
4. Path.
A typical uniform Resource locator looks like this:
Http://zh.wikipedia.org:80/wiki/Special:Search?search= Railway &go=go
which
1. HTTP, is the protocol;
2. zh.wikipedia.org, is the server;
3.80, is the network port number on the server;
4./wiki/special:search, is the path;
5. Search= Railway &go=go, is inquiry.
Most Web browsers do not require users to enter "http://" parts of the Web page, because the vast majority of Web content is Hypertext Transfer Protocol files. Similarly, "80" is a common port number for Hypertext Transfer Protocol files, so it is not generally necessary to specify. In general, users simply type part of the Uniform Resource Locator (zh.wikipedia.org/wiki/Railways). Because the Hypertext Transfer Protocol allows the server to redirect the browser to another Web page address, many servers allow users to omit parts of the web address, such as www. Technically, the omitted page address is actually a different web address, and the browser itself cannot determine whether the new address is available, and the server must complete the redirected task. [edit this paragraph] URL structure Description about the URL structure is generally divided into two parts, one is the physical structure, and the other is the logical structure. The physical structure consists of a flat structure and a tree structure. The flat structure is that all pages in the site are at the root level, forming a flat physical structure. This is more suitable for small sites, because if too many files are placed in the root directory, making and maintenance is more troublesome. And the meaning of the tree structure in the first level of the directory is divided into multiple channels or branches for the directory, and then put on the directory under the page belongs to this channel, home, channel home, channel content is like the trunk, branches, leaves of the relationship. A logical structure is a logical or linked network diagram formed by links within a Web page. The better case is that the logical structure is consistent with the previous tree-like physical structure.

As shown in the diagram on the left
Homepage links to all Channels homepage, homepage is generally not directly linked to the content page, unless you very much want to push a few special pages, all the channel homepage is connected to the other channel homepage, the channel homepage is connected to the homepage of the website, the channel homepage is connected to the content page belonging to its own channel, and the channel homepage is not connected to the content All content pages are connected to the homepage of the site, all content pages are connected to their own upper-level channel home page, content pages can be connected to other content pages of the same channel, content pages are generally not connected to other channels ' content pages, and content pages can, in some cases, be linked to the content pages of other channels with the appropriate keywords.
URL Processing method
First, you need to pay attention to the length of the URL, in the URL is best not more than 3-5 keywords, if more than 5 keywords, the weight of the URL will be reduced accordingly.
Second, try not to repeat in the URL.
Finally, avoid using suffixes such as. exe as the end of the URL at the time of naming. [edit this paragraph] the role of the Uniform Resource Locator URL a Uniform Resource Locator (URL) is an address identification method that is defined to enable a client program to query a different information resource when there is a uniform access method. All resources on the Internet have a unique URL address.

The composition and meaning of the URL