"In cryptography, a salt is random data that is used as an additional input to a one-way function that hashes a password or passphrase. The primary function of salts is to defend against dictionary attacks and pre-computed rainbow table attacks."[1]

"Autoboxing is the term for getting a reference type out of a value type just through type conversion (either implicit or explicit). The compiler automatically supplies the extra source code which creates the object."[1]

Bang Methods

"Ruby methods that modify an object in-place and end in an exclamation mark are known as bang methods. By convention, the bang labels a method as dangerous."[1]

Mathematical Maturity

"... fearlessness in the face of symbols: the ability to read and understand notation, to introduce clear and useful notation when appropriate (and not otherwise!), and a general facility of expression in the terse - but crisp and exact language that mathematicians use to communicate ideas."[1]

"By nesting fragment caches, it ensures that caches can be reused even when content changes. When a change occurs to the top-most fragment cache, only that cache must be expired. Every nested cache of the parent can be reused, which provides a significant performance increase. A change to the most nested fragment cache would start a chain reaction to expire all parent caches."[1]

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