What is an S3 bucket?

It is a fundamental unit within Amazon AWS & it is simple storage service/ It is a container where you store objects (files, data etc) & used to organize & manage data within S3

What are the different S3 storage classes?

Amazon S3 offers a variety of storage classes like S3 standard, S3 standard infrequent access, S3 intelligent Tiering, S3 Glacier, S3 Glacier deep Archive, S3 outposts etc

What are the two retention modes supported by S3 Object Lock?

S3 objects lock supports two primary modes for object retention Governance & compliance

How do you configure a Lambda function to process events from S3 ?

When to consider using asynchronous invocation?