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@@ -1,3 +1,11 @@
 # hash
 
-Hash experiments.
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+This is a non-cryptographic hash (aka checksum) to verify data integrity.
+
+## API
+
+```go
+sum := hash.Bytes(data)
+```
+
+You can use `strconv.FormatUint(sum, 16)` to get a string in hexadecimal format.
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