Color Temperature (Kelvin) — The numerical measure of light color. Low Kelvin = warm/orange light. High Kelvin = cool/blue light. Daylight is approximately 5500K.
Light Source — Different sources emit different color temperatures: candles (~1800K), tungsten bulbs (~2800K), fluorescent tubes (~4000K), midday sun (~5500K), cloudy sky (~6500K), shade (~7500K).
RAW vs JPEG — Shooting RAW lets you change white balance in post with no quality loss. JPEG bakes in the white balance permanently, so getting it right in-camera matters more.
Mixed Lighting — Scenes with multiple light sources at different temperatures (e.g., window daylight + tungsten lamps) make it impossible to perfectly neutralize all colors simultaneously.