Learn in the textbookCloud Deployment Models and Operation Models
DefinitionPublic cloud (パブリッククラウド) is a model in which facilities prepared by a cloud provider are shared over the internet by many unspecified users.
ExplanationUsers do not buy their own equipment; once they sign up they can start within a short time, and they pay for what they use. Because many users split the facilities, the cost per company tends to stay low and it is easy to scale with rising or falling demand. On the other hand, settings and features must be chosen from what the provider offers.
AnalogyA laundromat, where many people take turns using the shop's machines. You do not buy a washer yourself; you pay only for each load.
Memory hook"Public" means open to everyone. Picture a public phone booth that anyone can use.