Glossary of Terms

Cycle
Synonym for period; ie, the number of results that can be returned before a random number generator starts to repeat itself.

Period
One of the common pitfalls of pseudo random number generators is that they will start repeating the same sequence of "random" numbers if given enough time. The number of results that can be returned before this happens is known as the generator's period. A good generator will have a very long period - possibly long enough that it's impractical to detect in practice.

PRNG
A common abbrivation of "Pseudo Random Number Generator".

Pseudo Random Number Generator
A method or process that creates what looks like random numbers. Their effectiveness varies widely.

RNG
A common abbrivation of "Random Number Generator". May or may not refer to a pseudo random number generator.

Seed
This is a value used to initialize the random number generator's internal state. Because a pseudo random number generator is ultimately based on math, two instances of the same generator initialized with the same seed will return the same sequence of "random" numbers. The ideal size of the seed value depends on the generator.