Functions in Mathematica are carefully set up so that you normally do not have to know how they work inside. But particularly for numerical functions that use iterative ...

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 ...

The Experimental Functions Package contains functions that are being considered for official inclusion in future versions of Mathematica.

ButtonBox[boxes] is a low-level box construct that represents a button in a notebook expression.

CellEventActions is an option for Cell that gives a list of actions to perform when specified events occur in connection with a cell in a notebook.

DynamicWrapper[e, expr] represents an object that displays as e, but dynamically updates the expression expr whenever that object is visible on screen.

LinkConnect["name"] connects to a MathLink link created by another program.

MakeExpression[boxes, form] is the low-level function used in Mathematica sessions to construct expressions from boxes.

On[symbol::tag] switches on a message, so that it can be printed. On["name"] switches on a named group of messages.On[s] switches on tracing for the symbol s. On[m_1, m_2, ...

lhs :> rhs or lhs :> rhs represents a rule that transforms lhs to rhs, evaluating rhs only after the rule is used.