Unless you have to use deflate/zlib/gzip/zip for compatibility or you're very constrained in amount of memory, you should always prefer zstd over deflate - it's always both faster and compresses better, so there is no tradeoff and using deflate is just wasteful.
Google's brotli is a close competitor and got supported in Chrome first, so HTTP uses that more than it uses zstd.
zstd has a very wide range of compression levels to tradeoff compression ratio for CPU time, much wider than the difference between gzip -1, gzip -6 (default) and gzip -9. zstd -3 is default. zstd -1 is very fast, zstd -19 compresses really well.
zstd also has a long range mode, for archives that contain the same file a gigabyte away. gzip's window is only 32KB in size, so it can't notice any repetitions more than that far away.
LZ4 by the same author as zstd aims at even faster compression, at the cost of worse compression ratio. It makes sense to use over fast network. Google snappy and LZO are the usual competitors.
When you want better compression than zstd (at the cost of CPU time, both during compression and during decompression), use PPMD for natural language text or source code and use LZMA (xz) for other things.
Google's brotli is a close competitor and got supported in Chrome first, so HTTP uses that more than it uses zstd.
zstd has a very wide range of compression levels to tradeoff compression ratio for CPU time, much wider than the difference between gzip -1, gzip -6 (default) and gzip -9. zstd -3 is default. zstd -1 is very fast, zstd -19 compresses really well.
zstd also has a long range mode, for archives that contain the same file a gigabyte away. gzip's window is only 32KB in size, so it can't notice any repetitions more than that far away.
LZ4 by the same author as zstd aims at even faster compression, at the cost of worse compression ratio. It makes sense to use over fast network. Google snappy and LZO are the usual competitors.
When you want better compression than zstd (at the cost of CPU time, both during compression and during decompression), use PPMD for natural language text or source code and use LZMA (xz) for other things.