StringQ (Built-in Mathematica Symbol)

StringQ[expr] gives True if expr is a string, and False otherwise.

LengthWhile (Built-in Mathematica Symbol)

LengthWhile[list, crit] gives the number of continuous elements e_i starting at the beginning of list for which crit[e_i] is True.

Rational (Built-in Mathematica Symbol)

Rational is the head used for rational numbers.

XMLObject (Built-in Mathematica Symbol)

XMLObject["type"] represents the head of an XML object in symbolic XML.

Real (Built-in Mathematica Symbol)

Real is the head used for real (floating-point) numbers.

MapAll (Built-in Mathematica Symbol)

MapAll[f, expr] or f //@ expr applies f to every subexpression in expr.

Dimensions (Built-in Mathematica Symbol)

Dimensions[expr] gives a list of the dimensions of expr. Dimensions[expr, n] gives a list of the dimensions of expr down to level n.

Annotating & Combining Graphics (Mathematica Guide)

In Mathematica's unified symbolic framework, graphics are treated just like any other expression—to be displayed, arranged, annotated, or manipulated using any of ...

Functional Programming (Mathematica Guide)

Long viewed as an important theoretical idea, functional programming finally became truly convenient and practical with the introduction of Mathematica's symbolic language. ...

TuringMachine (Built-in Mathematica Symbol)

TuringMachine[rule, init, t] generates a list representing the evolution of the Turing machine with the specified rule from initial condition init for t steps. ...