<programming, operating system> A variable that is bound in the current environment. When evaluating an expression in some environment, the evaluation of a variable consists of looking up its name in the environment and substituting its value. Most programming languages have some concept of an environment but in Unix shell scripts it has a specific meaning slightly different from other contexts. In shell scripts, environment variables are one kind of shell variable. They differ from local variables and command line arguments in that they are inheritted by a child process. Examples are the PATH variable that tells the shell the file system paths to search to find command executables and the TZ variable which contains the local time zone. The variable called "SHELL" specifies the type of shell being used. These variables are used by commands or shell scripts to discover things about the environment they are operating in. Environment variables can be changed or created by the user or a program. To see a list of environment variables type "setenv" at the csh or tcsh prompt or "set" at the sh, bash, jsh or ksh prompt. In other programming languages, e.g. functional programming languages, the environment is extended with new bindings when a function's parameters are bound to its {actual arguments} or when new variables are declared. In a block-structured procedural language, the environment usually consists of a linked list of activation records. (1999-01-26)

An environment variable is a dynamic-named value that can affect the way running processes will behave on a computer. They are part of the environment in which a process runs.

<programming, operating system> One of the variables accessible to a Unix shell process, including {environment variables} (e.g. $HOME), command line arguments (e.g. $1) and local variables (e.g. $input_file). Other {operating systems} have similar variables. (1999-01-26)

Evolution in Variable Environment (EVE) is a computer program designed to simulate microbial cellular behavior in various environments. The prediction of cellular responses is a rapidly evolving topic in systems biology and computational biology.

In computer programming, a variable is an abstract storage location paired with an associated symbolic name, which contains some known or unknown quantity of information referred to as a value; or in simpler terms, a variable is a named container for a particular set of bits or type of data (like integer, float, string etc...).

Variable bitrate (VBR) is a term used in telecommunications and computing that relates to the bitrate used in sound or video encoding. As opposed to constant bitrate (CBR), VBR files vary the amount of output data per time segment.

A random variable (also called random quantity, aleatory variable, or stochastic variable) is a mathematical formalization of a quantity or object which depends on random events. It is a mapping or a function from possible outcomes in a sample space to a measurable space, often the real numbers.

Market environment and business environment are marketing terms that refer to factors and forces that affect a firm's ability to build and maintain successful customer relationships. The business environment has been defined as "the totality of physical and social factors that are taken directly into consideration in the decision-making behaviour of individuals in the organisation.