Optimism is a mental attitude reflecting a belief or hope that the outcome of some specific endeavor, or outcomes in general, will be positive, favorable, and desirable. A common idiom used to illustrate optimism versus pessimism is a glass filled with water to the halfway point, where the optimist is said to see the glass as half full and the pessimist sees the glass as half empty. The term derives from the Latin optimum, meaning best. Being optimistic, in the typical sense of the word, is de
A tuple is a finite ordered list of elements. In mathematics, an n-tuple is a sequence (or ordered list) of n elements, where n is a non-negative integer. There is only one 0-tuple, an empty sequence. An n-tuple is defined inductively using the construction of an ordered pair.
Tuff: An igneous rock that contains the debris from an explosive volcanic eruption. It often contains fragments of bedrock, tephra and volcanic ash. The specimen shown here is about two inches (five centimeters) across.