Are you wondering what all the talk is about?
Wanting to learn to use PHP?
Read on!
From what you hear being said about it you could be forgiven for thinking it to
be the panacea for all that ails the Web development world. There are those who
would argue that you would be right in thinking that. While I may not quite go
to that extreme, I will join those who will not argue against the notion! It is
indeed a very useful weapon in the Web Designer’s arsenal. So what exactly is
it? Where can you get it? How much does it cost? How do you use it? Whoa there,
Nelly! That’s what this little series is all about. This is an introduction to
PHP intended to give you a foundation for its use and to guide to resources you
can use to get deeper into the PHP world. PHP is gaining ground quite rapidly
and is being accepted and used in some very demanding and traditionally cautious
environments. There are good reasons, so you are encouraged to read on!
PHP started its life in 1994 in the mind and hands of one Mr. Rasmus Lerdorf.
Recognizing the virtue of his creation a number of very talented programmers
have lent their skills to its development, and have included a number of
complete rewrites along the way. The latest release, PHP4 comes from a company
called Zend. PHP is an Open Source project, meaning that its source code is
available for you to study, use and modify, should you so wish. Its name
originally stood for Personal Home Page, but it has since adopted “PHP Hypertext
Preprocessor” (GNU, the open source project is fond of recursive names like its
own “GNU’s Not Unix”.) PHP is free. It can be downloaded from www.PHP.net or,
for PHP4, www.Zend.com.
PHP is a Server Side scripting language. Compare that to JavaScript, which is a
client side scripting language. The main difference between Server Side and
Client Side concerns what data you can manipulate and when. If you want to
manipulate data that is in databases on the server, then you need to use
server-side technology. The web pages themselves also reside on the server, and
so are also manipulated by server side technology. Once the page has been
displayed on the client machine you need client side technology to manipulate
data associated with it. For example, if you have displayed a form on which your
site visitor is entering data and you wish to validate that data, allowing the
visitor to make corrections, before sending the data back to the server, then
all that validation must be performed by client side technology.
PHP code runs on the server, not on the client. If you write PHP code, perhaps
extracting data from a MySQL database, you are writing server side code. On the
other hand, if you write some JavaScript, it is included with the HTML that is
the web page and is sent down to the client computer for processing. The HTML
code in the page and the JavaScript are both examples of client side
technologies. To communicate between server side and client side technologies,
data must be transmitted back and forth between the server and client computers.
More about all this later on!
Before you can take advantage of PHP extensive capabilities, it must be
installed and available on the server hosting your website. Here’s some good
news! PHP is platform friendly. It runs on Windows, Linux and many flavors of
UNIX, so the chances are it can be installed on your server if it’s not already
there. Because of its popularity most hosting companies these days offer support
for PHP. If you’re not sure about yours, call and ask them. If they don’t
support it, ask them why not, then choose another host!
Other server side languages, competitors if you like, include PERL, ASP (Active
Server Pages) (&ASP.Net), JSP (Java Server Pages), Alaire’s Cold Fusion and
others. PHP has some advantages over its competitors. It’s free – a tough price
to beat! It’s very efficient, making it capable of handling millions of daily
hits on one inexpensive server (check out the benchmarks on http://www.Zend.com
) It’s portable, meaning that it’s easily moved from one platform to another
(it’s not identical on Windows and Unix/Linux, but it’s very close – there would
be only a few things to be changed.) It integrates with a variety of Database
Management Systems (DBMS) including MySQL, which is also free! The list of DBMS
is quite extensive and includes support for any systems that provides an Open
Database Connectivity Standard (ODBC) driver, as most do.
Another big advantage of PHP is that it’s easy to learn. That’s what we’re all
about here. As previously mentioned, this introductory piece is to lead you into
a new tutorial series that will provide a foundation for you to begin using PHP.
We will be covering the basics of the language and providing some usable
examples. In addition, we will be guiding you to some resources that you can use
to increase the depth of your understanding of PHP and to expand the range of
things you can accomplish with it. Gone are the days of the old static web page
(well, almost!) Welcome to the dynamic world of interactivity and database
connectivity on the Web!
Continue to the next part of this Tutorial
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