What is the PMF and CDF of the difference between two discrete random variables?

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I have found a lot of references for the continuous case but I can't seem to find much information about how to find the PMF and CDF of the difference for two discrete r.v. for which we know their CDF and PMF.

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If $X$ and $Y$ are two independent discrete random variables, the PMF of $Z=X-Y$ is the convolution of $X$ and $-Y$:

$$P(Z=z)=\displaystyle\sum_{k=-\infty}^{\infty}P(X=k)P(Y=z-k)$$

Source: https://stats.stackexchange.com/a/450958/40817