PHP Section 1 Introduction to PHP_Basic of PHP

What is PHP:

PHP is a scripting language that runs on computers. Its founder is Rasmus Ledolf. The first two PHP versions were developed by this person. The original intention of developing the PHP language was relatively simple. It is for maintaining personal web pages, counting traffic, etc. In order to accelerate development and optimization, the author released it on June 8, 1995, which is also open source.

What are the application scenarios of PHP:

PHP is a language with a wide range of applications, especially in the development of network programs. Generally speaking, PHP is mostly executed on the server side. By executing PHP programs, web pages are generated for browsers to read. In addition, it can also be used to develop command line scripts and user-side GUI applications. PHP can be executed on many different servers, operating systems, and platforms, and can also be combined with many database systems. There is no cost to use PHP. Yes, it is completely free. The official organization PHP Group provides complete program source code, allowing users to modify, compile, and expand it for use.

What are the main data types of PHP:

PHP mainly has the following four scalar types:

• integer (integer)
• Floating point type (float)
• Boolean (boolean)
• String

Two composite types:

• Array (array)
• object

Two special types

• NULL
• resource

What are the commonly used function libraries in PHP:

The power of a language depends on clear and powerful function libraries and class libraries. The built-in diverse functions are one of the main features of PHP. These open code functions provide a variety of different functions, such as file processing, FTP, string processing, etc. The usage of these functions is similar to C language (such as printf), which is one of the reasons why PHP is so popular.

In addition to the built-in functions, PHP also provides many extension function libraries (extensions), such as various database connection functions, Data compression functions, graphics processing, etc. Some extension function libraries need to be obtained from PECL (PHP Extension Community Library).

What are the mainstream open source frameworks for PHP:

The official framework of PHP is the Zend framework. It has been developed since 2005 and has entered a mature stage. Although there is still controversy in the industry about the direction of the PHP framework, the use of the framework has become very common in actual production.

Other commonly used PHP frameworks include: Yii, CodeIgniter, CakePHP, Symfony, QeePHP/FleaPHP, ThinkPHP, CakePHP, etc. Using these frameworks can make projects faster and simpler to deploy and more agile in development efficiency, but On the other hand, learning to use these frameworks requires additional learning costs.

What are the mainstream versions of PHP:

PHP has developed from 1.0.0 to today's 5.*.*, 6.0 is also under development; and 5.2 .10 is no longer maintained and optimized; the current major versions are 5.3.10 and 5.4.0.

Major version reference.

Reference source:

Wikipedia

PHP Manual