What it is: A top-level container in S3 where you store objects.

What it’s for:

• Organize data by purpose (e.g., logs bucket, uploads bucket).
• Apply policies, encryption, and lifecycle settings at bucket scope.

Key ideas:

• Bucket name is globally unique (across all AWS accounts).
• A bucket exists in a specific Region.
• You can enable versioning and default encryption at bucket level.

Exam cues:

• “bucket name already taken” → global uniqueness.
• “control access to an entire bucket” → bucket policy.

Hard words:

• *globally unique* /ˈɡloʊbəli juːˈniːk/: duy nhất toàn cầu
• *scope* /skoʊp/: phạm vi