The Common Cold

I don't know why they call it the common cold, that seems to imply there are several types of cold, but that there is one type, the "common" one, that is most frequent. My problem with the term is that every cold I've ever had is pretty unique. My current one has no cough (thankfully), but a very runny nose and a sore head. I'm hoping the worst is over, it started yesterday, I was miserably last night and this morning, but now I feel more or less OK. Back to work tomorrow I hope.