Open source software: Open source software is a new term, which is defined as software whose source code can be used by the public, and the use, modification and distribution of this software are not restricted by the license. Open source software is usually copyright, and its license may contain some restrictions: Intentionally protect its open source status, announcement of the author's identity, or control of development. "Open source" is being registered as a certification mark by public interest software organizations, which is also a means to create a formal definition of open source.

BSD UNIX: software based on "BSD" license developed by University of California at Berkeley. Many UNIX commercial editions are directly based on BSD source code or mostly borrowed from its design.

Linux: It has grown from a research project of Finnish college students to the most popular non-Microsoft operating system in recent six years. Initially, it was only designed for PCs, but now it supports Palm Pilots, large supercomputers with 64-bit Digital Alphas chips, and almost anything in between. Compared with the traditional operating system, it is more efficient, reliable and advanced. It includes compilers, libraries, various tools from FreeSoftware Foundation, and thousands of open-source products. Linux platform is the foundation of a small but rapidly growing commercial industry, and it is also a hotbed of software innovation. It is developed by commercial companies and freelance programmers scattered around the world based on GPL.

Perl language: "transmission belt of Internet", which is the basis of dynamic content of most web servers, is widely used in scripting language programming and automatic document processing. It was developed by Perl Research Institute based on the Artistic License Agreement.

WU-FTPD: the most popular FTP server on the Internet, which is used in almost all FTP sites. Originally developed by Bryan O'Connor on Louis Street of Washington University, it is now maintained by Academ Consulting Services and many volunteers (licensed by BSD).

browser: Firefox, Mozilla Firefox, commonly known as "Firefox" in Chinese, is an open source web browser that uses Gecko engine (ie non-IE kernel) and can run on various operating systems such as Windows, Mac and linux. Developed by Mozilla Foundation and hundreds of volunteers, Firefox was originally named "Phoenix", later renamed "Mozilla Firebird", and then changed to its current name. By August, 212, Firefox occupied 23% of the world.

Eclipse is an open source and extensible development platform based on Java. In itself, it is just a framework and a set of services for building a development environment through plug-in components. Eclipse comes with a standard set of plug-ins, including the Java Development Kit (JDK).

database: Hadoop is a distributed system infrastructure developed by Apache foundation. Users can develop distributed programs without knowing the underlying details of the distribution. Make full use of the power of cluster for high-speed operation and storage.

Web server: Apache HTTP Server (Apache for short) is an open source web server of Apache software foundation, which can run in most computer operating systems. Because of its multi-platform and security, it is widely used and is one of the most popular web server-side software. It is fast, reliable and can compile interpreters such as Perl/Python into the server through simple API extensions.