Evening is the period between the late afternoon and night when daylight is decreasing, around dinner time. Though the term is subjective, evening is typically understood to begin before sunset, during the close of the standard business day (about 6 pm) – and extend until dusk, the beginning of night. Evening thus spans the period of twilight, but begins before it and depending on definition may extend past its end.
In the rural American South, "evening" often describes the entire late afternoon, especially when the main meal of the day, dinner, is taken in the early afternoon; evening is thus anytime after dinner.
Informally, the term "evening" is used in place of "night", especially in the context of an event which takes place over the course of said "evening".
Source: en.wikipedia.org/wiki/Evening - 04.08.2010
Day and Night
How close and yet fascinating is the change of light and dark – day and night – and the fullness of the shading between.