On-line Information on Functions, Objects, and Calls
DESCRIPTION:
Provides the S-PLUS user with information on Functions, Objects, and Calls.
USAGE: 
?
?name
?object
?name(object, ...)
?methods(name)
OPTIONAL ARGUMENTS:
name:
a name or a character string giving the name of a function or operator. If omitted, documentation on ? is given (this documentation).
object:
the name of an S-PLUS object. Documentation will be offered on all the classes of objects from which the object inherits.
name(object, ...):
a proposed call, typically to a generic function, with the first argument being some (existing) S-PLUS object. Documentation will be offered on the function name itself and on all methods for name that might be used when the call is actually evaluated. However, the call is not evaluated: this use of ? is usually to decide what would happen if some proposed computation were done.
methods(name):
all possible methods for function name will be presented, based on the functions available on the current search list.
DETAILS:
In the cases where documentation is offered on all classes or methods, the options are presented to the user via the menu function. All the possibilities (as a character vector) are returned (invisibly) as the value of ?. Not all the proposed documentation need exist: ? does not check for the existence of the documentation when it constructs the menu.
SEE ALSO:
help , topic , menu .
EXAMPLES: 
?plot   # help on plot function
?myfit  # documentation for all the classes of object myfit
?"+"    # addition (and other arithmetic) Note the need for quotes
?plot(myfit)    # tell me about the plot methods for myfit
?">"(obj, 0)    # tell me about the ">" methods for obj