PHP is broadening its appeal.
What is it?
PHP has joined the mainstream.
Zend Technologies has not
only partnered with IBM to put enterprise-strength PHP on the
iSeries platform,
but has even persuaded Microsoft to stop treating PHP as a threat
and start supporting it. It has been promised that PHP on IIS and
Windows, previously painfully slow, will catch up with performance
on Apache.
According to the Tiobe
Community Programming Index, over the past year PHP has moved
from fifth to fourth in terms of skills availability, having
overtaken C++,
and is rapidly catching up on
Visual
Basic.
PHP is an open source, HTML-embedded scripting language, used
for server-side web applications that generate dynamic web pages,
providing an alternative to Microsoft's
Active
Server Pages and Sun's
Java Server
Pages. It can be downloaded and learned quickly from free
web-based sources, and has an active community to help developers
with support and code.
Where did it originate?
Originally written by Rasmus Lerdorf to maintain his online CV
and Personal Home Page (hence the acronym) PHP was picked up by
Zend founders Zeev Suraski and Andi Gutmans in 1997. They
transformed it over the next two releases, adding the Zend Engine
in 2000. The latest version is PHP 5.2.5, released in November
2007.
What's it for?
PHP mostly runs on the web sever to generate HTML web pages, but
is also used for command line scripting for Unix, Linux or even
Windows, and less often, for GUI-based desktop applications.
There are a number of frameworks for working with PHP, most
conspicuously the forthcoming
Zend Framework, and the
Zend Studio Integrated Development Environment (IDE). Lesser-known
options include CakePHP,
PRADO and
Symfony. For those
with a background in classic Rapid Application Development, there
is even a version of Delphi for PHP.
What makes it special?
Perl has CPAN, the Comprehensive Perl Archive Network. The PHP
equivalent is Pear, the PHP
Extension and Application Repository, a framework and distribution
system for free PHP code components. PHP's supporters claim it has
C's elegant syntax and Perl's powerful performance, without the
complexity of either. PHP also supports a very wide range of
databases, from the most widely used commercial and open source,
like Oracle,
IBM DB2,
Sybase,
MySQL and
PostgreSQL, to rare and legacy databases like Informix and
Ingres. PHP's functionality can easily be extended with C
programming.
How difficult is it to master?
Enough PHP can be picked up in a few hours to make you
productive, but more advanced skills will need time and patience. A
background in the languages PHP borrows from, such as C, Perl or
Java, would give you a start.
Where is it used?
Because anyone can download and use PHP, it's hard to keep track
of where and how extensively it is used. There's a story that the
CIO of a global IT vendor denied his organisation used it, only to
be told later that his web operations depended on it. PHP is also
favoured by organisations with no full-time IT staff.
What systems does it run on?
Apache, IIS and other web servers, most Unix, Linux, Mac OSX and
Windows.
What's coming up?
PHP 6 is due for release any time now but development of PHP 5
will continue in parallel.
Training
For free tutorials, start with
www.php.org,
www.php.net or
devzone.zend.com.www.zend.com offers more formal training, and manages
certification.
Jobs and money
£25,000 to £40,000 depending on other skills -higher with C/C++
than with MySQL.