Compression

Concepts: paCompression

What They Want to Hear 'Snappy for interactive queries because it decompresses fast. Gzip for archival because it compresses more. Zstd is the emerging winner: Gzip-level compression at nearly Snappy-level speed.' That is the complete answer. They are testing whether you understand the speed-vs-ratio tradeoff, not whether you know the algorithms' internals.