Use a Web Host With PHP Support

If your server has activated support for PHP you do not need to do anything.

Just create some .php files, place them in your web directory, and the server will automatically parse them for you.

You do not need to compile anything or install any extra tools.

Because PHP is free, most web hosts offer PHP support.

parse
文法的に説明する、品詞を指摘する、語法を解説する
構文解析する

parse command line
コマンド・ラインを解析する

natural language parser
自然言語パーサー

pattern learning parser
パターン学習パーサー

What Can PHP Do?

PHP can generate dynamic page content
PHP can create, open, read, write, delete, and close files on the server
PHP can collect form data
PHP can send and receive cookies
PHP can add, delete, modify data in your database
PHP can restrict users to access some pages on your website
PHP can encrypt data
With PHP you are not limited to output HTML. 
You can output images, PDF files, and even Flash movies. 
You can also output any text, such as XHTML and XML.

encrypt
暗号化する

What is WordPress?

WordPress is a free and open source blogging tool and a content management system (CMS) based on PHP and MySQL, which runs on a web hosting service.

Features include a plug-in architecture and a template system. 

WordPress is used by more than 22.0% of the top 10 million websites as of August 2013.

WordPress is the most popular blogging system in use on the Web, at more than 60 million websites.

It was first released on May 27, 2003, by its founders, Matt Mullenweg and Mike Little, as a fork of b2/cafelog. 

As of February 19, 2014, version 3.8 had been downloaded more than 20 million times.

The license under which WordPress software is released is the GPLv2 (or later) from the Free Software Foundation.

What is PHP?

PHP ( Full name: PHP: Hypertext Processor ) is described by the creators them self like this:

"PHP is a widely-used general-purpose scripting language that is especially suited for Web development"

A Few things about PHP:

PHP files have a file extension of ".php", ".php3", or ".phtml"
PHP stands for PHP: Hypertext Preprocessor
PHP is a server-side scripting language, like ASP
PHP scripts are executed on the server
PHP supports many databases (MySQL, Informix, Oracle, Sybase, Solid, PostgreSQL, Generic ODBC, etc.)
PHP is an open source software
PHP is free to download and use


 PHP is an amazing and popular language!

It is powerful enough to be at the core of the biggest blogging system on the web (WordPress)!
It is deep enough to run the largest social network (Facebook)!
It is also easy enough to be a beginner's first server side language!

PHP Session Variables

When you are working with an application, you open it, do some changes and then you close it. 

This is much like a Session. 

The computer knows who you are. 

It knows when you start the application and when you end. 

But on the internet there is one problem: the web server does not know who you are and what you do because the HTTP address doesn't maintain state.

A PHP session solves this problem by allowing you to store user information on the server for later use (i.e. username, shopping items, etc).

 However, session information is temporary and will be deleted after the user has left the website. 

If you need a permanent storage you may want to store the data in a database.

Sessions work by creating a unique id (UID) for each visitor and store variables based on this UID. 

The UID is either stored in a cookie or is propagated in the URL.

propagate
〔植物・動物・昆虫などが〕繁殖［増殖］する
〔電波・音波・光・振動などが〕伝わる、伝搬する