$Language (Built-in Mathematica Symbol)

$Language is a list of strings which give the names of languages to use for messages.

$Messages (Built-in Mathematica Symbol)

$Messages gives the list of files and pipes to which message output is sent.

$NewSymbol (Built-in Mathematica Symbol)

$NewSymbol is a global variable which, if set, is applied to the name and context of each new symbol that Mathematica creates.

$NumberMarks (Built-in Mathematica Symbol)

$NumberMarks gives the default value for the option NumberMarks, which specifies whether ` marks should be included in the input form representations of approximate numbers.

$ScriptCommandLine (Built-in Mathematica Symbol)

$ScriptCommandLine is a list of strings giving the elements of the command line with which the standalone Mathematica script was invoked.

$SystemID (Built-in Mathematica Symbol)

$SystemID is a short string that identifies the type of computer system on which Mathematica is being run.

$TimeUnit (Built-in Mathematica Symbol)

$TimeUnit gives the minimum time interval in seconds recorded on your computer system.

Complex Numbers (Mathematica Tutorial)

You can enter complex numbers in Mathematica just by including the constant I, equal to Sqrt[-1]. Make sure that you type a capital I. If you are using notebooks, you can ...

Core Language How to Topics (Mathematica Overview)

Work with Variables and Functions Work with Lists Work with Rules

Chini Equations (Mathematica Tutorial)

Chini equations are a generalization of Abel and Riccati equations. This solves a Chini equation.