HoldRest is an attribute which specifies that all but the first argument to a function are to be maintained in an unevaluated form.
Intersection[list_1, list_2, ...] gives a sorted list of the elements common to all the list_i.
MultilineFunction is an option for UnderscriptBox and related box objects that specifies what to do when the contents of a box object are too long to fit on one line.
Notebook[{cell_1, cell_2, ...}] is the low-level construct that represents a notebook manipulated by the Mathematica front end.
SpellingOptions -> {opt_1 -> val_1, opt_2 -> val_2, ...} is an option for notebooks that specifies settings for spell checking.
SqrtBox
(Built-in Mathematica Symbol) SqrtBox[x] is a low-level box construct that represents the displayed object Sqrt[x] in notebook expressions.
StyleData["style"] is a low-level representation of the contents of a style definition cell.StyleData["style", " environment"] represents the contents of a style definition ...
TimesBy
(Built-in Mathematica Symbol) x *= c multiplies x by c and returns the new value of x.
$ContextPath is a global variable that gives a list of contexts, after $Context, to search in trying to find a symbol that has been entered.
When you make a definition in the form f[args]=rhs or f[args]:=rhs, Mathematica associates your definition with the object f. This means, for example, that such definitions ...