Docker introduced an ambiguity in the meaning of the word "container". The word existed before Docker, and it was about sandboxing. Docker introduced the analog

Docker introduced an ambiguity in the meaning of the word "container". The word existed before Docker, and it was about sandboxing. Docker introduced the analogy of the shipping container, which as ranger207 says, is about sandboxing at the service of distribution. The two meanings - sandboxing and distribution - have coexisted ever since, sometimes causing misunderstandings and frustration.