| Term | Meaning |
|:-----|:--------|
| **Attribute** | Defines concrete visual styling for a visual element (Foreground color, Background color, TextStyle). |
| **BackgroundColor** | A property of `Attribute` describing the background text color. |
| **Color** | Base terminal color (supports TrueColor and named values like White, Black, Cyan, etc.). |
| **ForegroundColor** | A property of `Attribute` describing the foreground text color. |
| **Glyph** | A graphical representation of a character. |
| **Rune** | Unicode character. |
| **Scheme** | Maps `VisualRole` to `Attribute`, defining visual element appearance (color and style) based on semantic purpose. |
| **Style** | Property of `Attribute` for font-like hints (bold, italic, underline). |
| **VisualRole** | Semantic role/purpose of a visual element (Normal, Focus, HotFocus, Active, Disabled, ReadOnly). |