WordCharacter (Built-in Mathematica Symbol)

WordCharacter represents a letter or digit character in StringExpression.

$Context (Built-in Mathematica Symbol)

$Context is a global variable that gives the current context.

$InitialDirectory (Built-in Mathematica Symbol)

$InitialDirectory gives the initial directory when the current Mathematica session was started.

$MachineAddresses (Built-in Mathematica Symbol)

$MachineAddresses gives a list of strings specifying the current IP addresses associated with the computer on which Mathematica is being run.

$MachineDomains (Built-in Mathematica Symbol)

$MachineDomains is a list of strings giving the names of the current network domains associated with the computer on which Mathematica is being run.

$MachineName (Built-in Mathematica Symbol)

$MachineName is a string that gives the assigned name of the computer on which Mathematica is being run, if such a name is defined.

$SharedVariables (Built-in Mathematica Symbol)

$SharedVariables is the list of variables currently being shared among parallel kernels.

$UserName (Built-in Mathematica Symbol)

$UserName gives the login name of the user who invoked the Mathematica kernel, as recorded by the operating system.

Manipulating Notebooks (Mathematica Overview)

Cells as Mathematica Expressions Notebooks as Mathematica Expressions Manipulating Notebooks from the Kernel

MathLink Developer Guide - Linux (Mathematica Overview)

Supported Development Platforms Installing the MathLink Components Building MathLink Programs