From The Free On-line Dictionary of Computing (27 SEP 03) :
formal methods
Mathematically based techniques
for the specification, development and verification of
software and hardware systems.
Referentially transparent languages are amenable to symbolic
manipulation allowing program transformation (e.g. changing
a clear inefficient specification into an obscure but
efficient program) and proof of correctness.
Oxford FM archive
http://www.comlab.ox.ac.uk/archive/formal-methods.html)">(http://www.comlab.ox.ac.uk/archive/formal-methods.html).
(1996-05-15)