Linux adoption refers to the uptake of the Linux operating system by homes, organisations and governments. Linux migration refers to the change over to Linux from other operating systems.

History
The high level of access granted to Linux's internals has led to Linux users traditionally tending to be more technically-inclined than users of Microsoft Windows and Mac OS. Linux's roots in the Unix operating system mean that in addition to graphical configuration tools and control panels available for many system settings and services, it is often either easier or necessary to use plain-text configuration files to configure the OS. While user access to these files and utilities is controlled by the system administrator, and in theory the user does not need to worry about them, in practice the administrator and user are often the same person on a desktop system.

Power users
As local governments come under pressure from institutions such as the World Trade Organization and the International Intellectual Property Alliance, some have turned to open source software as an affordable, legal alternative to both pirated material and expensive computer products from Microsoft, Apple and the like.
The spread of free software affords some leverage for these countries when companies from the developed world bid for government contracts (since a low-cost option exists), while furnishing an alternative path to development for countries like India and Pakistan that have many citizens skilled in computer applications but cannot afford technological investment at "First World" prices.

In the preamble to the bill, the Peruvian government stressed that the choice was made to ensure that key pillars of democracy were safeguarded: "The basic principles which inspire the Bill are linked to the basic guarantees of a state of law."

Brazil's PC Conectado program
City of Munich has chosen to migrate its 14,000 desktops to Debian-based LiMux [3]
US Department of Defense, use and develop open source software
City of Vienna, has chosen to start migrating its desktop PCs to Debian-based Wienux [4]
Spain has been noted as the furthest along the road to Linux adoption [5], for example with Linux distribution LinEx
State owned Industrial and Commercial Bank of China (ICBC) is rolling out Linux in all of its 20,000 retail branches as the basis for its web server and a new terminal platform. (2005) [6]
In 2005 the Peruvian government voted to adopt Open Source across all its bodies. The 2002 response to Microsoft's critique is available online [7].
In January 2006, Venezuelan open source law goes into effect, mandating a two year transition to open source in all public agencies. [8]
In April 2006, the U.S. Federal Aviation Administration announced that it had completed a migration to Red Hat Enterprise Linux in one third of the scheduled time and saved 15 million dollars.[9]
The government of Pakistan established a Technology Resource Mobilization Unit in 2002 to enable groups of professionals to exchange views and coordinate activities in their sectors and to educate users about free software alternatives. GNU/Linux is an option for poor countries with little revenue available for public investment; Pakistan is employing open source software in public schools and colleges, and hopes to run all government services on GNU/Linux eventually.
The Ministry of Defense in Singapore began switching its computers from Microsoft to free software in 2004, while South Korea, China and Japan agreed to cooperate in creating new Linux-based programs.
The French Parliament have switched to using Kubuntu on desktop PCs. Government
Linux is often used in technical disciplines at universities and research centres. This is due to several factors, including that Linux is available free of charge and includes a large body of free/open source software. To some extent, technical competence of computer science and software engineering academics is also a contributor, as is stability, maintainability, and upgradability. IBM ran an advertising campaign entitled "Linux is Education" featuring a young boy who was supposed to be "Linux".

The Children's Machine (previously called the $100 laptop), is an inexpensive laptop running Linux, which will be distributed to millions of children as part of the One Laptop Per Child project, especially in developing countries.
Macedonia deployed 5,000 Linux desktops running Ubuntu across all 468 public schools and 182 computer labs (December 2005) [10]
Italian schools in Bolzano have switched to a custom distribution of Linux (FUSS Soledad GNU/Linux), which will be used by the 16,000 students in the area when they return on 12 September 2005. [11]
Brazil has around 20,000 Linux desktops running in elementary and secondary public schools.
The Netherlands has an initiative called "Open Source en standaarden in het onderwijs", in English "Open source and standards in education". [12]
Government officials of Kerala, India announced they will use only free software, running on the GNU/Linux platform, for computer education, starting with the 2,650 government and government-aided high schools. [13]
22,000 students in the U.S. state of Indiana were using Linux as of 2006[14] School and education

Sony's PlayStation 3 comes with a hard disk (20GB, 60GB or 80GB) with Linux designed to be installed easily on the system. Embedded systems
Linux is also used in some corporate environments as the desktop platform for its employees, with commercially available solutions including Red Hat Enterprise Linux, SUSE Linux Enterprise Desktop, and Linspire.

Ernie Ball, the guitar string manufacturers known for their famous Super Slinky guitar strings, have used Linux as their desktop operating system since 2000. [15]
Google, the search engine, uses several different Linux distributions on the desktop and a customised version of Red Hat Linux on over 100,000 servers[16].
Novell is currently undergoing a migration from Windows to Linux. Of their 5500 employees, 50% were successfully migrated as of April, 2006. This is expected to rise to 80% by November.[17]
Australian hotel booking site Wotif.com migrated from Windows to Linux servers in order to keep up with the growth of their business.[18]
California's Union Bank Migrates to Red Hat Enterprise Linux
European car maker Peugeot plans to deploy up to 20,000 copies of Novell's Linux desktop, SUSE Linux Enterprise Desktop, in 2007. Business
The primary driving forces behind Linux adoption can be summarized as:
Other reasons cited are:
Companies are engaging in Linux adoption and F/OSS:
The use of Linux on desktop PCs in corporations is being driven by employees requesting it, and by corporations seeing competitors successfully deploying Linux. [19]
In government, self-determination and vendor independence are valued, as well as the local software industry development that may surround the adoption of Linux.
In the developing world, recent WTO agreements have encouraged organizations to look to Linux as an alternative to using copyright-infringing software.
(For more details see Peruvian congress letter to Microsoft detailing the advantages it sees in Linux that influenced its 2005 Linux adoption decision)

Security
Reputation
Technological one-upmanship
Open source - it is visible what is being done with data, how the program works, and that it does what it is said to do.
Lack of vendor lock-in - data can usually be ported more easily because there is often less incentive to make this difficult than with proprietary software.
Long term usability (reduction in duplication and/or built in obsolescence) - open source software packaged with Linux usually lasts longer because repeated rollouts and "must have" updates are not part of the marketing model.
Low cost - most of the popular Linux distributions are available as a free download over the Internet, while Windows, depending on version and how it is purchased, costs between $199 and $299 per seat. Mac OS X costs $129 per seat, or $199 the family pack (5 licenses), and runs only on Apple hardware.
Core packages run across more platforms, and are often more standards compliant and interoperable. Major proprietary software tends to be compliant with, and interoperable with, its own manufacturer's software only, and is often hard to port to other platforms or systems.
At a professional level, Linux is configurable and robust.
Many of its core services, including expandability, and functions such as clustering, stability, and supercomputer-creation, are easier with Linux than many alternative common systems.
Upgrades are issued and problems fixed more quickly.
Other factors include the large number of languages Linux's interfaces are available in, the flexibility to customise it to local needs, and high quality remote management.
because it is the dominant trend in software production
to cause market disruption
because customers are demanding it, and
to move the value-adding to different areas. Advocacy

Diffusion or adoption (business)
Technology acceptance model
Technology lifecycle
Disruptive technology
Open source vs. closed source
Comparison of Windows and Linux
Fear, uncertainty and doubt (FUD)