For you non-Hams, QSL means, “I confirm your communication with me.” Today, this occurs most often when we upload our logs to one of several databases, such as the ARRL’s Logbook of the World.
Hams used to confirm contacts with paper, post-card sized, QSL cards. I still send them out. I recently worked a Hawaiian station. We both said we’d exchange real QSL cards. The Hawaiian station sent me an email today saying he had received mine and his was on its way to me. In the mean time, he sent me this electronic version.