Java Network Programming (3rd ed) [Electronic resources] نسخه متنی

Chapter 3. Basic Web Concepts

Java can do a lot more than create
flashy web pages. Nonetheless, many of your programs will be applets
on web pages, servlets running on the server, or web services that
need to talk to other web servers and clients. Therefore,
it's important to have a solid understanding of the
interaction between web servers and web browsers.

The Hypertext Transfer Protocol (HTTP) is
a standard that defines how a web client talks to a server and how
data is transferred from the server back to the client. The
architecture and design of the HTTP protocol is Representational
State Transfer (REST). HTTP can be used to transfer data in
essentially any format, from TIFF pictures to Microsoft Word
documents to DBase files. However, far and away the most common
format for data transferred over the Web and in some sense the
Web's native format is the
Hypertext Markup
Language (HTML). HTML is a simple standard for describing the
semantic value of textual data. You can say "this is
a header", "this is a list
item", "this deserves
emphasis", and so on, but you can't
specify how headers, lists, and other items are formatted: formatting
is up to the browser. HTML is a "hypertext markup
language" because it includes a way to specify links
to other documents identified by URLs. A URL is a way to
unambiguously identify the location of a resource on the Internet. To
understand network programming, you'll need to
understand URLs, HTML, and HTTP in somewhat more detail than the
average web page designer.