$Inspector (Built-in Mathematica Symbol)

$Inspector is a global variable which gives a function to apply when the inspector is invoked from an interrupt menu.

$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.

$NewMessage (Built-in Mathematica Symbol)

$NewMessage is a global variable which, if set, is applied to the symbol name and tag of messages that are requested but have not yet been defined.

$Packages (Built-in Mathematica Symbol)

$Packages gives a list of the contexts corresponding to all packages which have been loaded in your current Mathematica session.

$ProcessID (Built-in Mathematica Symbol)

$ProcessID gives the ID assigned to the Mathematica kernel process by the operating system under which it is run.

$VersionNumber (Built-in Mathematica Symbol)

$VersionNumber is a real number which gives the current Mathematica kernel version number, and increases in successive versions.

Displaying and Printing Mathematica ... (Mathematica Tutorial)

Depending on the purpose for which you are using a Mathematica notebook, you may want to change its overall appearance. The front end allows you to specify independently the ...

Levels in Expressions (Mathematica Tutorial)

The Part function allows you to access specific parts of Mathematica expressions. But particularly when your expressions have fairly uniform structure, it is often convenient ...