diff --git a/tar/storage/doc.go b/tar/storage/doc.go
new file mode 100644
index 0000000..6f67880
--- /dev/null
+++ b/tar/storage/doc.go
@@ -0,0 +1,12 @@
+/*
+storage is for metadata of a tar archive.
+
+Packing and unpacking the Entries of the stream. The types of streams are
+either segments of raw bytes (for the raw headers and various padding) and for
+an entry marking a file payload.
+
+The raw bytes are stored precisely in the packed (marshalled) Entry. Where as
+the file payload marker include the name of the file, size, and crc64 checksum
+(for basic file integrity).
+*/
+package storage