Key difference: PHP is a server-side scripting language that has its main implementation in web development. However, it can be used as a general-purpose programming language. ASP stands for Active Server Pages. It is commonly known as Classic ASP or ASP Classic. It is a server-side scripting environment that is developed and released by Microsoft.

PHP is a server-side scripting language that has its main implementation in web development. However, it can be used as a general-purpose programming language. PHP was originally created by Rasmus Lerdorf in 1995 and it is currently managed by The PHP Group. PHP originally stood for Personal Home Page, however it was later renamed. It now stands for PHP: Hypertext Preprocessor, a recursive acronym. PHP is free software released under the PHP License, as is incompatible with the GNU General Public License (GPL) due to restrictions on the usage of the term PHP.

PHP is an open source, server-side, HTML embedded scripting language. It can basically perform any task that other CGI programs can, but it is mainly used to create dynamic Web pages. Its main advantage is that it is compatible with many types of databases. Furthermore, PHP can talk across networks using IMAP, SNMP, NNTP, POP3, or HTTP.

PHP includes a command-line interface capability and can be used in standalone graphical applications. PHP commands can be embedded directly into an HTML source document rather than calling an external file to process data. In the HTML document, the PHP script is enclosed within special PHP tags. Due to these tags, the programmer can alternate between HTML and PHP instead of having to rely on heavy amounts of code to output HTML. Also, as PHP is executed on the server, the client cannot view the PHP code.

ASP stands for Active Server Pages. It is commonly known as Classic ASP or ASP Classic. It is a server-side scripting environment that is developed and released by Microsoft. It was Microsoft's first server-side script engine for dynamically generated web pages. ASP was originally released as part of the Windows NT 4.0 Option Pack. It was meant to be an add-on to Internet Information Services (IIS). Since, then ASP has been superseded by ASP.NET, another product by Microsoft.

ASP is mainly used to create and run dynamic, interactive Web server applications. It also allows one to combine HTML pages, script commands, and COM components to create interactive Web pages and powerful Web-based applications. It also makes it easier to develop and modify the said Web applications.

After its original release, there have been two version releases. The ASP 2.0 introduced six built-in objects to the original, which were Application, ASPError, Request, Response, Server, and Session. ASP 3.0 introduced some additional enhancements such as Server.Transfer method, Server.Execute method, and an enhanced ASPError object. Additionally, ASP 3.0 also enabled buffering by default and optimized the engine for better performance. However, as of May 2013 there are no planned upgrades to ASP.

Some differences between PHP and ASP:

• ASP only runs on IIS installed on a Windows platform server
• PHP code runs faster than ASP.
• ASP is built on COM based architecture, which is an overhead for the server whereas PHP code runs in its own memory space.
• PHP programs can run on various platforms like Linux, Unix, Windows and Solaris whereas ASP is mainly associated with Windows platforms.
• PHP has inbuilt features like ftp, email from a web page or even encryption mechanisms but in ASP such features are not built in.
• PHP is based on C++ language and the syntax used in PHP is quite similar to C/C++. ASP’s syntax is based on the syntax of Visual Basic.
• PHP can connect to various databases, mainly MySQL, whereas ASP mainly uses MS-SQL.
• PHP codes tend to easier than ASP codes.

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