What is the origin of the idiom "clear as mud" and when to use it?

The idiom "clear as mud" is used to humorously describe something that is not clear or easily understood at all. The origin of this phrase lies in its ironic and contradictory nature. Mud is, by nature, opaque and messy, so comparing something to mud implies a lack of clarity and simplicity. This expression is often used when someone is trying to explain something, but their explanation is confusing or convoluted. It highlights the fact that the information or explanation provided is anything but clear.