URLs and URIs

URL

• Uniform Resource Locator
• Uniform resource locator
• yes www The unified resource positioning mark , In short URL Namely web Address , Be commonly called “ website ”
• URL It is a concise representation of the location and access method of resources obtained on the Internet , Is the address of standard resources on the Internet
• It's a representation of the location of information on the world wide web service program of the Internet
• The resources available on the Internet can be represented by simple strings , This document describes the syntax and semantics of this string . These strings are called ：“ Uniform resource locator ”（URL）

form

• URL It's made up of three parts ： resources type 、 Where resources are stored Host domain name 、 resources file name
• HTTP URL In the form of

http://<host>:<port>/<path>?<searchpart>

• file URL In the form of

file://<host>/<path>

URI

• Uniform Resource Identifier
• Uniform resource identifiers
• A string used to identify the name of an Internet resource
• URI Defined by a scheme that includes deterministic syntax and related protocols
• This kind of logo allows users to （ Including local and Internet ） The resources interact with each other through specific protocols
• Anything that can uniquely identify a resource is called URI

form

• The first part is the agreement （ Or service mode ）; The second part is the host where the resource is stored IP Address （ Sometimes a port number is also included ）; The third part is the specific address of the host resource
• Specifically URI The format of

[ The name of the agreement ]://[ user name ]:[ password ]@[ Server address ]:[ Server port number ]/[ route ]?[ Query string ]#[ fragment ID]

difference

URI and URL Defines what resources are , but URL It also defines how to access resources .
URL It's a kind of concrete URI, It is URI A subset of , It's not just a unique identification of resources , It also provides information to locate the resource .
URI It's a semantic abstraction , It can be absolute , It can also be relative , and URL You have to provide enough information to locate , Absolutely .