Reusing pieces of HTML code is a common way of making web sites (or web applications) more consistent, reliable, and more manageable. Even a small web site consisting of perhaps 20 or 30 web pages can benefit from reusing code for header and footer sections, for example. If the same header or footer is used across all the pages on the site, it makes sense to put the header and footer code in separate files, and then call those files to insert their contents where required.

PHP offers two statements that can be used for inserted the contents of one file inside another: include() and require(). These two statements are virtually identical, with the only real difference being that if require() fails, it gives a fatal error, whereas if include() fails it just gives a warning. For this reason I tend to use the include() statement as it just seems slightly more friendly.

So, to include the contents of a file called header.inc inside a web page called index.php, you would just need to insert the following line of code (wrapped in PHP opening and closing tags) inside index.php.

Include 'header.inc';

As PHP takes no notice of the extension used for the included file, you can use whatever extension you want to. Be careful though, if you put passwords inside an include file with a .inc extension, they will be visible. You can get around this by putting include files that contain sensitive information outside the document tree to prevent people from browsing to them.

In Part 2 we'll look at the use of functions when developing web sites and applications.

What Is PHP?

The full form of PHP is Hypertext PreProcessor and is a server-side scripting language. The PHP code can be combined with regular HTML tags and parsed on the server. The creator of PHP, Rasmus Lerdorf first displayed the language in the form of a Perl script . In 1997 it was adapted by Andi Gutmans and Zeev Suraski to use a C-written compiler. They completely reconstructed the original PHP into the web language that we know and use today.

Uses of PHP

It is used in the creation of dynamic web pages. Web developers like it because of its fast parsing and flexibility and versatility. PHP is a popular tool for managing a form's data after it is submitted and comes built in with many different interfaces and API's. It has database capability built into the language, the most common database being MySQL. Typically the PHP can connect to any SQL enabled database.

The Syntax of PHP is similar in structure to Perl and C where curly braces { } define blocks of code and semi-colons specify the end of a statement PHP is as easy to learn as Perl. It maintains all the traditional loops, if/else, and subroutines that are expected in a programming language. One difference between the two is that the code'?' is embedded in with the HTML; you could however, use a separate file. The PHP code is different from HTML code by use of the opening and closing tags. When it finds a PHP file, it tells the server to scan through for these tags, and execute the code in between them. The server recognizes a PHP enabled file by its extension, .php. These are essentially HTML files with PHP codes in them.

Getting Started

To start PHP requires a server with PHP installed and a simple ASCII text editor such as Notepad or VI, eMacs, Kate, etc. for a UNIX/Linux machine.

What are the problems faced by PHP?

It is case sensitive. For example if you name a variable $MyVar, you cannot call it as $myvar or $mYvAr. In case you forget to close your curly brackets, then it helps to indent lines inside the curly braces so that any missing braces can be spotted easily.

I think we would all like to make money online. The notion of making money from home is a popular one. To be able to have money passively coming in day in and day out would be wonderful. However theory can be very different from actuality.

The goal of this article is to improve your odds of success. When it comes to building any website you need to understand the core principles. A good website will provide value to its visitors.

To provide such value you need to offer good content. Good content is king in the online hierarchy. In order to provide good content you need to do quality research. By the way quality research will become your daily routine.

The question is where to start so as to get positive results. The two places I always begin with are the article directories and forums. Both of these provide information relative to demand and interest.

The article directories will tell you how popular a topic is based upon the number of page views any given article receives on any given subject. The forums will tell you what people are looking for relative to this and the level of interest.

This will also enable you to understand how to communicate directly to these folks based upon their specific needs and problems. You need to be able to relate in order to communicate effectively.

Effective communication will lead to building long lasting relationships which will be profitable for all parties concerned.

Once you have this information you will need a good site builder so that you can build valid web pages that can be understood by both your human readers and the search engines. This way your site will appear in the search engines for any given keyword you choose to come up for.

This will bring lots of quality targeted traffic that will convert to sales and as a result you will make money day in and day out.

To learn how to put all this together select any of the links provided.