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+# Compression Decoders
+
+Compression decoders read from one input stream (an `io_reader` called `src`)
+and write to an output stream (an `io_writer` called `dst`). Wuffs'
+implementations have one key method: `decode_io_writer`, named after the
+operation (decoding) and the type of the destination (an
+[`io_writer`](/doc/note/io-input-output.md)). It incrementally decompresses the
+source data.
+
+This method is a [coroutine](/doc/note/coroutines.md), and does not require
+either all of the input or all of the output to fit in a single contiguous
+buffer. It can suspend with the `$short_read` or `$short_write`
+[statuses](/doc/note/statuses.md) when the `src` buffer needs re-filling or the
+`dst` buffer needs flushing. For an example, look at the
+[example/zcat](/example/zcat/zcat.c) program, which uses fixed size buffers,
+but reads arbitrarily long compressed input from stdin and writes arbitrarily
+long decompressed output to stdout.
+
+
+## Dictionaries
+
+TODO: standardize the various dictionary APIs, after Wuffs v0.2 is released.
+
+
+## Implementations
+
+- [std/deflate](/std/deflate)
+- [std/gzip](/std/gzip)
+- [std/lzw](/std/lzw)
+- [std/zlib](/std/zlib)
+
+
+## Examples
+
+- [example/library](/example/library)
+- [example/zcat](/example/zcat)
+
+
+---
+
+See also the general remarks on [Wuffs' standard library](/doc/std/README.md).
