The Latin word variatio entered Castilian as a variation. That’s what the act and result of variation is called: change, alter.
The concept has multiple uses depending on the context. In the field of genetics, variation refers to changes that occur in the genes of a species or population. Genetic variation is linked to evolution. Alternative forms of genes located at the same position on homologous chromosomes are known as alleles, the expression of which defines various traits. If there are many alleles for a gene, one may prevail over the others and thus natural selection occurs. Therefore, genetic variation contributes to the evolutionary process.
In the field of music, variation refers to an altered repetition within the framework of a composition. It is a technique that leads to reiterate, with alterations, a rhythm, a melody or another element throughout the work. The main topic, therefore, is imitated in the subtopics. These imitations are known as variations. For mathematics, variations are subsets that have the same number of elements as the set in question, although with differences in the order or in a particular element. The idea of variation is also used in colloquial language to name a modification that allows something to look different from what it was or was, transforming its characteristics, its shape, etc. It is also a registered change in something. Suppose a person usually makes an apple pie with raisins. One afternoon, however, he decides to use plums. This means that he has introduced a variation of the usual recipe. Take the case of the Gross Domestic Product (GDP) of a country. The change in GDP or GDP over the last decade, for example, shows how the data has changed over ten years.