Computing Laws, Theorems and Aphorisms

There are plenty of laws, theorems and aphorisms out there, apart from Moore’s and Murphy’s, that computer people could use. They sometimes come handy in meetings and emails! Just using them could, at times, mean standing on the shoulders of giants. I plan to keep this as an ongoing post… shall keep adding till it gets too long!

Laws and Theorems

• Amdahl’s Law: used to find the maximum expected improvement to an overall system when only part of the system is improved
• Metcalfe’s Law: the value of a network is proportional to the square of the number of connected users of the system (n²)
• Conway’s Law: Any piece of software reflects the organizational structure that produced it
• Grosch’s Law: Computer performance increases as the square of the cost. If computer A costs twice as much as computer B, you should expect computer A to be four times as fast as computer B
• Little’s Law: The long-term average number of customers in a stable system L is equal to the long-term average effective arrival rate, λ, multiplied by the (Palm‑)average time a customer spends in the system, W; or expressed algebraically: L = λW.
• Gustafson’s Law: Any sufficiently large problem can be efficiently parallelized
• Gilders Law: bandwidth grows at least three times faster than computer power - See more at: http://www.netlingo.com/word/gilders-law.php#sthash.zGRjAR00.dpuf
• Mooers Law: An information retrieval system will not be used if it is more painful for the user to have information than not to have it
• Parkinsons Law: Programs expand to fill all available memory
• Millers Law: All discussions of incremental updates to Bugzilla will eventually trend towards proposals for large scale redesigns or feature additions or replacements for Bugzilla
• Wirths Law: Software gets slower faster than hardware gets faster
• Brooks Law: Adding manpower to a late software project makes it later
• Greenspuns Law: Any sufficiently complicated C or Fortran program contains an ad hoc, informally specified, bug-ridden, slow implementation of half of Common Lisp
• Hintjens Law of Concurrency: e = mc², where, e = effort, m = mass of code, c = colliding threads

Aphorisms and Quotes

• Carnegie Mellon’s Professor Richard Pattis’s collection
• Yale’s tribute to Alan Perlis - Epigrams in Computing
• Edsger Dijkstra’s, Quotes
• David Wiseman’s, Laws of Computing
• Fred Brooks’s, Quotes
• Don Knuths, Quotes
• Tony Hoare’s, Quotes
• Quotes listed on Paul Graham’s site
• Murphy’s Computer Laws