SystemOpen["target"] opens the specified file, URL, or other target with the associated program on your computer system.
TextureCoordinateScaling is an option to Plot3D and similar functions that specifies whether arguments supplied to a texture coordinate function should be scaled to lie ...
TimeZone is an option for DateString, AbsoluteTime, and related functions that specifies the time zone to use for dates and times.
Toggler
(Built-in Mathematica Symbol) Toggler[x] represents a toggler button with setting x, that toggles between True and False. Toggler[Dynamic[x]] takes the setting to be the dynamically updated current value ...
TraceOriginal is an option for Trace and related functions which specifies whether to test the form of each expression before its head and arguments are evaluated.
VectorColorFunctionScaling is an option for graphics functions which specifies whether arguments supplied to a vector color function should be scaled to lie between 0 and 1.
WordSeparators is an option for Read, Find, and related functions that specifies the list of strings to be taken as delimiters for words.
$ByteOrdering gives the native ordering of bytes in binary data on your computer system.
$FrontEnd is a global variable that specifies to what front end object, if any, the kernel is currently connected.
$NewSymbol is a global variable which, if set, is applied to the name and context of each new symbol that Mathematica creates.