PHP3 Chinese documentation (transferred)_PHP tutorial

Chapter 1 Getting Started with PHP3
What is PHP3?
PHP3.0 version is a server-side HTML-embedded script description language.
What can PHP3 do?
Perhaps the most powerful and important feature of PHP3 is its database integration layer. It is incredibly simple to use it to complete a web page containing database functions. The databases listed below are currently supported.
Oracle
Adabas D
Sybase
FilePro
MSQL
Velocis
MySQL
Informix
Solid
dBase
ODBC
Unix dbm
PostgreSQL

A brief history of PHP
PHP has been conceived since the fall of 1994. Its founder is Rasmus Lerdorf. An early, unreleased version was used by him on his website to track who visited his online profile. The first version used by others was released in 1995 and was called Personal Home Page Tools. It contains a very simple syntax analysis engine that can only understand some specified macros and some common functions of the Home Page backend, such as guestbook, counter and some other materials. In mid-1995, the parsing engine was rewritten and named PHP/FI version 2.0. FI comes from another package written by Rasmus that can accept Html form data. He combined the Personal Home Page Tools script and the Form Interpreter, and added support for mSQL, and PHP/FI 2.0 was born. PHP/FI developed at an alarming rate, and other people began to improve and modify its source code.
It is difficult to give any precise statistics, but it is estimated that by the end of 1996, at least 15,000 WEB sites were using PHP/FI 2.0. By mid-1997, this number had grown to 50,000. In mid-1997, PHP's There have been some changes in development as well, as he has gone from Rasmus's pet project to a more organized group project. The syntax analysis engine was also rewritten by Zeev Suraski and Andi Gutmans. This engine forms the basis of PHP3. Most of the common code in PHP/FI has been rewritten and introduced into PHP3.
Today (mid-1998), many commercial products such as C2's StrongHold web server and Red Hat Linux have begun to support PHP3 or PHP/FI. Based on conservative inferences based on the numbers provided by NetCraft, there are now about 150,000 WEB sites are using PHP or PHP/FI. Prospectively, there are far more of these sites on the Internet than those running Netscape's flagship Enterprise server.
Use PHP3 for HTTP authentication
The HTTP authentication function can only be used when PHP is running as an Apache module. In Apache's module PHP script, you can use the Header() function to send an "Authentication Required" message to the client's browser, causing the browser to pop up an input window for username/password. After the name and password are passed, the URL containing the PHP script will be called again, using the $PHP_AUTH_USER, $PHP_AUTH_PW, and $PHP_AUTH_TYPE variables representing the username, password, and confirmation method respectively. Currently only the "BASIC" confirmation method is supported.