Why do I need to know about Domain Names?

Nearly all the time you use the it you will use or need to refer to domain names.

You will call domains up directly via telnet, Ftp or gopher. On the WWW you will either call domains explicitly via URL or implicitly via hypertext links.

On email you will mail somebody at a domain:

A typical email address looks like user-name@domain.name.

For example dave@cs.cf.ac.uk where

• dave is my user-name
• @ is the standard email separator of name and domain-name
• cs.cf.ac.uk is the domain of this department.

URL's are just as easy to read

URL stands for Uniform Resource Locator.

A typical WWW URL is of the form IPtype://domain.name.

For example: http://www.cs.cf.ac.uk

where:

• The IPtype is the internet protocol type used for storage and transmission. On the WWW this is typically Hypertext Transmission Protocol, http, but can be telnet, ftp, gopher, news (USENET news) or even mailto (email).
• :// is standard URL punctuation to separate IPtype from domain.

• Domain name of site some time the domain name you are used to will be prefixed by www (as in www.cs.cf.ac.uk, www.bbc.co.uk), sometimes the host is named explicitly.
• Following the domain name the directory path and name of file can be specified. We will see this shortly.