Ceramic decoration techniques have evolved over centuries, with underglaze and overglaze methods standing out as two distinct approaches. Underglaze decoration involves applying pigments or designs directly onto the unfired clay body before the glaze is added. This technique requires high-temperature firing (typically 1200-1400°C), which bonds the decoration permanently with the clay. The colors appear muted but highly durable, as they're protected beneath the glassy glaze layer.

Overglaze decoration, also called enamel decoration, occurs after the initial glaze firing. Artists apply paints or precious metals onto the already glazed surface, then fire the piece at lower temperatures (700-900°C). This method allows for vibrant colors and intricate detailing, but the decoration remains more vulnerable to wear as it sits atop the glaze.

Key differences include:

1. Application timing: Underglaze before glazing, overglaze after

2. Firing temperatures: Underglaze requires higher heat

3. Durability: Underglaze lasts longer

4. Color vibrancy: Overglaze offers brighter hues

5. Texture: Underglaze becomes part of the surface, while overglaze creates a raised design

Traditional Chinese porcelain often combines both techniques, using underglaze blue designs with overglaze enamels to create magnificent polychrome effects. Modern potters choose between them based on desired aesthetics and functional requirements of their ceramic pieces.