Definitions for "Stellar evolution"
The changes that take place in the characteristics of stars as they age.
(stellar=of a star) The different phases in the lifetime of a star, from its formation out of gas and dust, to the time after its nuclear fuel is exhausted. Based on observations of stars at various stages of their evolution, astronomers have developed a general theory of stellar evolution, by which the Sun is a typical "main sequance" star, in the middle of its evolutionary lifespan.
The processes by which stars condense out of primordial clouds, ignite nuclear burning processes, exhaust their nuclear fuel, and end their existence either in some kind of explosion or as a slowly dying cinder.
Standard candles are celestial objects with known luminosities. This allows them to be used as distance indicators as their distance can be inferred by comparing their apparemnt and absolute magnitudes. Examples include Type Ia supernovae and Cepheids.