S3 Exam frequency ⭐⭐⭐⭐⭐

Amazon S3

Amazon Simple Storage Service

StorageObject StorageSAA-C03
Last organized

Highly durable, scalable regional object storage accessed through APIs or HTTP.

Basic Information

FieldDetails
English nameAmazon S3
Full nameAmazon Simple Storage Service
Chinese description对象存储
Japanese descriptionオブジェクトストレージ
Exam frequency⭐⭐⭐⭐⭐
Often confused withEBS / EFS / S3 on Outposts

In one sentence

S3 is AWS object storage: buckets are management boundaries, objects hold data and metadata, and keys uniquely identify objects inside a bucket.

Core purpose

  • An object can be up to 5 TB; uploads larger than 5 GB must use multipart upload.
  • Buckets and objects are private by default. IAM, bucket policies, Block Public Access, presigned URLs, and encryption control access.
  • Versioning protects history, Lifecycle manages transitions and expiration, while replication and Object Lock add protection.

Exam focus

  • Choose S3 for objects, static assets, logs, backups, and data lakes.
  • Select Standard, IA, Glacier, or Intelligent-Tiering from access frequency, retrieval time, and total cost.
  • CloudFront with a private S3 origin is a common secure distribution pattern.

Common misconceptions

  • Slashes in a key only create a prefix-like view; S3 is not a POSIX file system.
  • Versioning retains billable historical versions and is not a free backup.

Key takeaway

Bucket holds objects; keys locate them; policies control access; Versioning protects history; Lifecycle controls cost.

CloudFront, IAM, KMS, CloudTrail, AWS Backup.