A Web stack is the term used to refer to software stacks for Web development environments. The stack of software, also called a solution stack, is frequently, but not always, made up of open source software to run dynamic Web sites. Web stacks contain an operating system, Web server, database server and programming language. One of the most most well-known Web stacks is LAMP, which stands for the following:

L  - Linux as the operating system
A - Apache as the Web server
M - MySQL as the RDBMS
P  - PHP is the the scripting language

In many cases, where a 'P' exists in the acronym it stands for PHP, but Perl or Python may also be substituted for the programming language. Here is a list of several alternative Web stacks and what software makes up the acronym. For more information, definitions to the various operating systems, programming languages, databases and Web servers can be found below.

Webopedia Definitions:

Linux
A freely distributable open source operating system that runs on a number of hardware platforms. The Linux kernel was developed mainly by Linus Torvalds. Because it's free, and because it runs on many platforms, including PCs and Macintoshes, Linux has become an extremely popular alternative to proprietary operating systems.

Mac OS
The official name of the Macintosh operating system. Earlier versions were called System x.x, where x.x were the version numbers.

Microsoft Windows
A family of operating systems for personal computers. Windows provides a graphical user interface (GUI), virtual memory management, multitasking, and support for many peripheral devices.

Solaris
A Unix-based operating environment developed by Sun Microsystems. Originally developed to run on Sun's SPARC workstations, Solaris now runs on many workstations from other vendors.

Apache Web server
Often referred to as simply Apache, a public-domain open source Web server developed by a loosely knit group of programmers. Core development of the Apache Web server is performed by a group of about 20 volunteer programmers, called the Apache Group. However, because the source code is freely available, anyone can adapt the server for specific needs, and there is a large public library of Apache add-ons.

IIS
Short for Internet Information Server, Microsoft's Web server that runs on Windows NT platforms. Because IIS is tightly integrated with the operating system, it is relatively easy to administer.

MySQL
MySQL is an open source RDBMS that relies on SQL for processing the data in the database. MySQL provides APIs for the languages C, C++, Eiffel, Java, Perl, PHP and Python. MySQL is most commonly used for Web applications and for embedded applications and has become a popular alternative to proprietary database systems because of its speed and reliability. MySQL can run on UNIX, Windows and Mac OS.

PostgreSQL
PostgreSQL is an open source database system that began as an enhancement to the POSTGRES research prototype DBMS. Where POSTGRES used the PostQuel query language, PostgreSQL uses a subset of SQL.

Oracle
Oracle Corporation is the largest software company whose primary business is database products. Historically, Oracle has targeted high-end workstations and minicomputers as the server platforms to run its database systems. Its relational database was the first to support the SQL language, which has since become the industry standard.

SQL Server
Generically, any database management system (DBMS) that can respond to queries from client machines formatted in the SQL language. When capitalized, the term generally refers to either of two database management products from Sybase and Microsoft. Both companies offer client-server DBMS products called SQL Server.

Firebird
Firebird is a RDBMS offering many ANSI SQL standard features that run on Linux, Windows and a variety of Unix platforms. Firebird offers concurrency, high performance and powerful language support for stored procedures and triggers. Firebird is open source and as such, it is completely free of any registration, licensing or deployment fees.

PHP
Self-referentially short for PHP: Hypertext Preprocessor, an open source, server-side, HTML-embedded scripting language used to create dynamic Web pages. In an HTML document, PHP script (similar syntax to that of Perl or C ) is enclosed within special PHP tags. Because PHP is embedded within tags, the author can jump between HTML and PHP (similar to ASP and Cold Fusion) instead of having to rely on heavy amounts of code to output HTML. And, because PHP is executed on the server, the client cannot view the PHP code.

Perl
Perl is a programming language developed by Larry Wall, especially designed for processing text. Because of its strong text processing capabilities, Perl has become one of the most popular languages for writing CGI scripts.

Python
An interpreted, object-oriented programming language developed by Guido van Rossum. Python is very portable because Python interpreters are available for most operating system platforms. Although Python is copyrighted, the source code is open source, and unlike GNU software, it can be commercially re-sold.

Ruby
Ruby is a simple but powerful object-oriented programming language (everything in Ruby is an object), created by Yukihiro Matsumoto. It can be used to write servers, to experiment with prototypes, and for everyday programming tasks. Ruby is open source and freely available for both development and deployment.

Ruby on Rails
Abbreviated as RoR, Ruby on Rails (also referred to as just Rails) is an open source Web application framework, written in Ruby (object-oriented programming language), for developing database-backed Web applications.

Vangie 'Aurora' Beal - Writer, www.Webopedia.com
Last updated: September 07, 2007
 

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