Oracle Cloud Infrastructure offers two distinct storage class tiers to address the need for both performant, frequently accessed "hot" storage, and less frequently accessed "cold" storage. Storage tiers help you maximize performance where appropriate and minimize costs where possible.
Use Object Storage for data to which you need fast, immediate, and frequent access. Data accessibility and performance justifies a higher price to store data in the Object Storage tier.
Use Archive Storage for data to which you seldom or rarely access, but that must be retained and preserved for long periods of time. The cost efficiency of the Archive Storage tier offsets the long lead time required to access the data.
Unlike Object Storage, Archive Storage data retrieval is not instantaneous.
Reference:
https://oracledbwr.com/oracle-cloud-infrastructure-object-storage-service/