A poster title color scheme refers to the combination of colors used in the design of a poster's title. This includes the selection of primary, secondary, and accent colors that complement each other and contribute to the overall aesthetic and readability of the poster. The color scheme should be visually appealing, convey the theme or message of the poster, and ensure that the text is easily readable. It is important to consider the color theory, which involves understanding how different colors can evoke emotions and how they interact with each other.