The discussion clarifies the differences between the Wigner function and the Q function in quantum optics, noting that the Wigner function is a quasi-probability distribution that can take negative values, while the Q function is always positive. Despite the positivity of the Q function, it does not imply that quantum mechanics simplifies to classical statistical mechanics, as calculating expectation values requires integrating against the P-function, which can exhibit negative values and singularities. Wigner, Q, and P functions form a one-parameter family of quasi-probability distributions that can be interconverted through convolution or deconvolution with Gaussians. When representing quantum states with one of these functions, observables must be represented by the dual quasi-probability representation, with the Wigner representation being unique in its self-duality. This explanation enhances understanding of the relationships between these functions in quantum optics.