Keywords: Innocence, Purity, Integrity, Neutrality, Cleanliness, Clarity, New Beginnings, Hope, Ignorance, Emptiness, Exposure, Isolation, Sterility, Boredom.
White contains an equal balance of all the colors of the spectrum, inherently implying equality and neutrality. Most of white’s connotations revolve around being unsullied, untainted, devoid of corruption. Traditionally, white has been associated with purity, cleanliness, innocence, new beginnings, and peace (e.g. a white dove.)
It's a color often observed in nature, the color of milk, snow, chalk, and a common color of animal coats, like a white horse, polar bear, dogs, cats, etc...
Rabbis wear white robes on Yom Kippur, the Jewish Day of Atonment, to symbolize the new beginning, the clean slate of the new year that follows the atonement for the previous year’s sins.
In alchemy, white or "Albedo" is the second of four major stages on the path to the philosopher's stone.
Weddings are another new beginning in which white is used for its symbolism. In this context, the white is also meant to represent the purity or chastity of the bride (although the meaning of this tradition no longer applies in modern times).
Interestingly, white is the traditional color of mourning in China and some African cultures, and used to be a color of morning reserved for medieval European queens. We can see this as a more conceptual interpretation of the concept of a new beginning; one has ended this phase of existence and is moving on to the next.
Too much white can have an isolating or sterilizing effect. You can utilize it in your images to create a sense of emptiness around a focal point, or wield its symbolism to imply peace, hope, or clarity.