Google Cloud Storage is Google’s proposal for storing data in the cloud by using its own infrastructure. It brings some of the features that power the entire Google Cloud Platform, such as high availability, scalability, and performance. If you are familiar with other data-storage systems like Amazon S3, OpenStack Swift, and storage in Azure, you can consider Cloud Storage in the same family.
Typical applications of such services involve storing medium- to large-sized data that is served to clients across the globe and does not need to be processed in the cloud. Examples are online backups, avatars, internal logs, media ...