In practice thereThere are many practical examples of data exhibitingwhose valid values are restricted within a small range. ofA validtrivial valueshash allfunction ofis which area suitable forchoice processing{{clarify|date=Januarywhen 2012}}such usingdata needs to act as a triviallookup hashkey. functionSome examples includinginclude:
* [[month]] in the year (1–12) – see [[#C example 1|C examples]] below
* [[day]] in the month (1–31)
* [[day of the week]] (1–7)
* human lifespan{{clarify|date=January 2012}}age (0–130) – e.g. lifecover actuary tables, fixed term mortgage
* [[ASCII]] characters {{clarify|date=January 2012}} (0–127), encompassing common mathematical operator symbols, digits, punctuation marks and English language alphabet
