What is the function of url

The function of URL is to identify information resources on the Internet and uniformly address the services provided by the Internet. Through the URL, we can reach any place to find what we need, such as files, databases, images, news, etc.

URL is the abbreviation of Uniform Resource Loctor, which is a unified resource locator. It is a tool that identifies where there are information resources on the Internet and unifies the services provided by the Internet. Addressing system. Function of URL: Through URL, you can reach any place to find what you need, such as files, databases, images, news groups, etc. It can be said that URL is the address book on the Internet.

URL generally consists of three parts, each part is as follows:

1. Server identifier. The type of server to be accessed can be determined by selecting the server identifier. The server identifier in the URL can include HTTP://, FTP://, GOPHER://, TELNET://, NWES://, etc. They are respectively designated to use Hypertext Transfer Protocol to connect, to use File Transfer Protocol to connect, to connect with the GOPHER server, to connect with the TELNET session, and to connect with the USENET news group.

2. Information resource address. The information resource address is composed of two parts. One is the machine name, which is used to indicate the machine where the resource exists, and the other is the communication port number (port number), which is the communication port number used when connecting. Port is a software identifier used by the Internet to identify specific information services. Its setting range is an integer between 0 and 65535. Generally, the standard port number is used and does not need to be written out.

Non-standard port numbers will be used when special services are required. In this case, they must be written out, such as . Common port numbers for Internet services, such as the standard port number for HTTP is 80, the standard port number for TELNET is 23, the standard port number for FTP is 21, and so on.

3. pathname. The path name is the complete file name of the resource on the machine where it is located. Generally, this option is given only when the user knows where the resource he is looking for is.

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