Random

Random (pronounced ran-duhm)

(1) Proceeding, made, or occurring without definite aim, reason, or pattern; lacking any definite plan or prearranged order; haphazard.

(2) In statistics, of or characterizing a process of selection in which each item of a set has an equal probability of being chosen (the random sample); having a value which cannot be determined but only described probabilistically.

(3) Of materials used in building and related constructions, lacking uniformity in size or shape.

(4) Of ashlar (stonework), laid without continuous courses and applied without regularity:

(5) In slang (also clipped to “rando” and some on-line sources insist “randy” is also used), something or someone unknown, unidentified, unexpected or out of place; anything odd or unpredictable (not necessarily a pejorative term and used as both noun & adjective).

(6) In slang, someone unimportant; a person of no consequence (always a pejorative).

(7) In printing, the sloping work surface at the top of a compositor's workbench on which type is composed (also called a bank and use now almost exclusive to the UK).

(8) In mining, the direction of a rake-vein.

(9) Speed, full speed; impetuosity, force (obsolete).

(10) In ballistics, the full range of a bullet or other projectile and thus the angle at which a weapon is tilted to gain maximum range (obsolete).

(11) In computing (as pseudorandom), mimicking the result of random selection.

1650s: From the earlier randon, from the Middle English randoun & raundon, from the Old French randon, a derivative of randir (to run; to gallop) of Germanic origin (related to the Old High German rinnan (to run) (from which Modern French gained randonnée (long walk, hike), from either the Frankish rant (a running) & randiju (a run, race) or the Old Norse rend (a run, race), both from the Proto-Germanic randijō, from rinnaną (run), from the primitive Indo-European r̥-nw- (to flow, move, run).  It was cognate with the Middle Low German uprinden (to jump up) and the Danish rende (to run).  The development of the adjective to mean “having no definite aim or purpose, haphazard, not sent in a special direction” evolved in the 1650s from the mid-sixteenth century phrase “at random” (at great speed) which picked up the fourteenth century sense from the Middle English noun randon & randoun (impetuosity; speed).  In English, the meaning closely mirrored that in the Old French randon (rush, disorder, force, impetuosity), gained from Frankish or other Germanic sources.  The spelling shift in Modern English from -n to –m was not unusual (seldom, ransom et al).  Random is a noun & adjective, randomness & randomosity are nouns, randomize is a verb and randomly is an adverb; the noun plural is randoms.

A “random person” is one variously unknown, unidentified, unexpected or out of place.

In general use, the meanings related to speed (full speed; force, trajectory of delivery etc) faded from use between the fourteenth & seventeenth centuries but persisted in the field of ballistics where “random” described the limit of the range of a bullet or other projectile (thus the angle at which a weapon was tilted to gain the maximum range.  Even that was largely obsolete by the early twentieth century but the idea of the angle being “a random” persists still in pockets in the UK to describe a sloping work surface on which printers compose pages (although few now use physical metal type).  The now familiar twenty-first century slang use can be either pejorative (someone unimportant; a person of no consequence) or neutral tending to the amused (something or someone unknown, unidentified, unexpected or out of place; anything odd or unpredictable).  The modern adoption appears to have its origin in 1980s US college student slang when “a person who does not belong on our dormitory floor” was so described; from this the hint of “inferior, undesirable” was perhaps inevitable.  “Rando” seems to be the standard abbreviation but some on-line sources also list “randy” which would seem to risk confusion or worse.

School lunch social engineering: Some sources recommend parents cut their children’s sandwiches in random ways.  The theory is it helps train their minds to accept change and helps them learn to adapt.

In computing, random access memory (RAM) had since the 1980s become familiar as one of a handful of the critical specifications of a computer (CPU, RAM, drive space) and the origin of the terms dates from IBM’s labs in the early 1950s when it was used to describe a new form of memory which could be read non-sequentially.  The modern RAM used by personal computers, servers, smart phones etc is an evolution from the original memory model; in the world of the early mainframes there was simply storage which could fulfil the functions now performed by both RAM and media like hard disks & solid state drives.  RAM is now a well-known commodity but the companion ROM (Read-Only Memory) is understood only by nerds and only an obsessional few of them give it much thought.  RAM volatile in that the contents are inherently temporary lost when the device is powered-down or re-started; it can thus be thought of as using static electricity for data storage.  That characteristic means it’s fast, affording the most rapid access by the CPU (Central Processing Unit) so is used to hold whatever data is at the time most in demand and that can be parts of the operating system, applications or documents.  ROM is non-volatile and whatever is written to ROM remains even if a device is switched-off; it’s thus used for essential, information like firmware and hardware information.

In mathematics and statistics, random does have precise definitions but in general use it’s used also as a vague synonym for “typical or average”.  To a statistician, the word implies “having unpredictable outcomes to the extent all outcomes are equally probable and if any statistical correlation is found to exist it will be wholly coincidental.  Thus, although all dictionaries list the comparative as more random and the superlative as most random, a statistician will insist these are as absurd as “very unique” although even among mathematicians phrases like “increasingly random” or “tending to randomness” are probably not unknown.  For others, the forms are useful and the colloquial use to mean “apropos of nothing; lacking context; unexpected; having apparent lack of plan, cause or reason” is widely applied to events, even those which to a specialist may not be at all random and may even be predictable.  For most of us, any sub-set of numbers which appears to have no pattern will appear random but mathematicians need to be more precise.  In the strict, technical sense, a true random number set exists only when two conditions are satisfied: (1) the values are uniformly distributed over a defined interval or set and (2) it is impossible to predict future values based on past or present ones.  In the pre-computer age, creating random number lists was challenging and subsequent analysis has found some of the sets created by manual or mechanical means were not truly random although those which were sufficiently large probably were functional for the purposes to which they were put.

“Random news” is something strange, unexpected and often amusing.    

Now, random number generators (RNG) are used and they can exist either in hardware or software and there are two types (1) pseudorandom number generators (PRNG) and true random number generators (TRNG).  A software algorithm, a PRNG emulates a TRNG by mimicking the selection of a value to approximate true randomness, the limitation being the algorithm being based on a distribution (the origin of the term pseudorandom) which can only produce something ultimately deterministic and predictable (although to determine the pattern can demand much computational power).  Relying on a seed number, if that can be isolated, other numbers can be predicted although, if the subset is large, for many purposes, what PRNGs generate is functional.  TRNGs don’t use an algorithm (although their processes can be represented by one) but are instead based on an unpredictable physical variable such as radioactive decay of isotopes, airwave static, or the behaviour of subatomic particles, the latter now favoured for their utterly unpredictable movements, now called “pure randomness”.  So random is the behaviour of subatomic particles that their observation appears to be immune to measurement biases which can (at least in theory) afflict other methods.

Random numbers are important in a number of fields including (1) statistical sampling and experimentation where it’s essential to select a random sample to ensure that the results are representative of the entire population, (2) cryptography where random numbers are used to generate the encryption keys which ensure the security of data and communications, (3) simulation and modelling where there’s a need to replicate real-world scenarios, (4) gaming & gambling where the need exists to create unpredictable outcomes and (5) randomized controlled trials (RCT), notably in medical and scientific research where true randomness is needed to assist in the assessment of the effectiveness of treatments, interventions, or policies.