Evolution is any process of growth or development that entails change. The word stems from the Latin evolutio meaning "unfolding" and before the late 19th century was confined to referring to goal-directed, pre-programmed processes such as embryological development. A pre-programmed task, as in a military maneuver, using this definition, may be termed an "evolution." After the publication of Charles Darwin's The Origin of Species in 1859, "evolution" became primarily associated with biological evolution as a non-guided process for the differentiation of forms of life from a common ancestor. Evolution can also refer to stellar evolution, chemical evolution, cultural evolution, spiritual evolution or the evolution of an idea. Other kinds of evolution include evolutionary algorithms (which include genetic algorithms) which attempt to mimic processes similar to biological evolution in a computer program, most frequently as an optimization technique and as an experimental framework for the computational modelling of evolution. It is also invoked as a concept in ideas on emergent order.