URL and URI

1, URI is a Uniform resource identifier, is a string used to identify an Internet resource name. This type of identification allows users to interact with any resource, including local and internet, through a specific protocol. The URI is defined by a scheme that includes a determination of syntax and related protocols. Consists of three components: the naming mechanism for accessing the resource, the host name that holds the resource, and the name of the resource itself, represented by the path.
For example, the URL of the file, the server mode with file, followed by the host IP address, file access path (that is, directory) and filename and other information. Directories and file names can sometimes be omitted, but the "/" symbol cannot be omitted.
Example: File://a:1234/b/c/d.txt represents the acquisition of resources using the FTP protocol, the resource target is a host of the 1234 port of the B directory under the C directory under the D.txt.
2, the URL is a unified resource positioning, is to be available from the Internet, the location of resources and access methods of a concise expression, the Internet is the address of the standard resources. Each file on the Internet has a unique URL that contains information that indicates the location of the file and how the browser should handle it.
For example, Baidu URL is http://www.baidu.com.

URL: A Uniform Resource locator is a  URL such as http://www.microsoft.com/  
URI: Generic resource Identifier  http://www.acme.com/support/suppliers.htm

URL and URI