The Linux operating system has become the leading alternative to the operating systems from Microsoft Corporation that are installed on almost all new personal computers which use x86-compatible microprocessors. It provides an excellent environment for carrying out econometric research. In this review, I will explain what Linux is, discuss its advantages and disadvantages from the point of view of an econometrician, and provide a number of references. Many of the references will take the form of `universal resource locators', or URLs, which can be accessed using a web browser. To save space, I will omit the preยฎx http:// from these URLs.
Linux is probably the best-known example of open-source' software, programs for which the source code is freely available on the Internet. Open-source software is free in the sense that it can be obtained without payment, and it is also free in the sense that users are allowed to modify it, but it is not free in the sense that anyone can do whatever they want with it. Almost all opensource software is copyrighted by its authors. It is released under a variety of dierent licences. The most commonly used is the GNU General Public Licence', or GPL, of the Free Software Foundation (www.fsf.org). The key feature of the GPL is that software released under it must always remain open. Anyone is free to modify GPL software, but if they distribute the modiยฎed software, they must make the source code available under the terms of the GPL. The Linux kernel and other key components of the operating system are released under the GPL, but many components are released under other, generally similar, licences.
Linux is named after Linus Torvalds, who started working on it in 1991 when he was a graduate student in Helsinki. It has thousands of authors, who collaborate via the Internet. Technically, Linux just refers to the core of the operating system, the so-called `kernel', which interacts directly with the hardware and supervises the operation of other programs. However, a working Linux system includes many other components, without which it would not be very