Ceramic capacitors are a type of capacitor that use ceramic materials as the dielectric, which is the insulating material between the conductive plates. They are widely used in electronic circuits due to their relatively low cost, compact size, and good frequency response. Ceram caps have high stability and can be made with different capacitance values. They also have a wide range of temperature coefficients that allow them to be used in various applications such as filtering, coupling, and decoupling circuits.