Communication is the practice of getting a specific thing understood by a specific audience, and adjusting when it is not. It covers writing, speaking, and the choices around both: what to include, what to leave out, what order to put it in, and which medium to use. The measure is what the audience came away with rather than what the communicator intended, so evidence of this capability is frequently evidence about somebody else's behaviour: what they did next, what they asked, whether they had to ask at all.
What communication is not
- It is not fluency, and a person who writes elegantly to nobody in particular is not demonstrating it. It is not volume: the learner who posts most often in a channel is not thereby communicating best, and may be communicating worst. It is not confidence in presentation, which is a delivery skill that frequently accompanies this capability and is regularly mistaken for it. It is not agreement, so a message that lands accurately and is rejected on the merits is a success rather than a failure. And it is not the same as writing quality: a grammatically imperfect message that produced the right action outperforms a polished one that produced confusion.