What type of data do you receive from Amazon S3, and what file formats are commonly used?

Amazon S3 stores objects, which are essentially blobs of data identified by a key. The data can be any binary or text format. Common file types include:

• CSV – plain text, comma‑separated values, easy to parse.
• JSON – structured, hierarchical data.
• Parquet – columnar storage optimized for analytics.
• Avro – binary format with schema.
• XML – markup language.
• Images/Audio/Video – binary media.

When retrieving data, you typically get the raw bytes and then deserialize based on the file type. S3 also stores metadata (content‑type, size, last‑modified) that can help determine how to process the object. For large datasets, you might use S3 Select or Athena to query directly without downloading the entire file.