Why do some web addresses have a ~ (tilde) in them?

WWW address can be broken up into three parts: 1) the protocol type, 2) the hostname 3) the file location. Three example addresses are:
http://www.fiu.edu
http://www.fiu.edu/orgs/english
http://www.fiu.edu/~jdoe01/resume.html

The protocol type is the http:// that appears at the beginning of *most* addresses. It stands for HyperText Transfer Protocol. This the system your connecting to how to process the request for information. Other protocols that can be addresses are https:// (secure http), ftp:// (file transfer protocol), news:// (USENET news) and gopher:// (to a gopher server).

The hostname is the section between // and /. These days, many www sites start with www.host.domain, but they don't have to. One very popular example is espnet.sportszone.com. Most sites, though are using it since it's easy to remember.

The third section specifies which file should be pulled up. In the first example above, there isn't a file specified, which means that the default file should be sent from the server. This file is usually called either index.html, index.htm or home.htm. The first example can also be written as
http://www.fiu.edu/index.html. The second example says look in the directory orgs for a directory called english and display the default file. In the third example, ~jdoe01 means look for username jdoe01, look in that person's home directory for a default directory (either called www or public_html), and in there look for a file called resume.html.

To finally answer the original question, all personal www pages are listed by their username, most, though not all, departmental web pages are available both with and without the tilde. The person maintaining the department's www pages will need to contact the FIU webmaster (webmaster@fiu.edu) regarding changes to the address.

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