Interestingly, gzip came after zip (some 3 years later)
They needed a new compress/decompress tool once IBM asserted their patent rights on the LZW algorithm used in the compress tool.
zip uses a different header for the compression stream, commonly known as the zlib format.
They also use different checksums at the end (CRC32 vs Adler32).
Also it should be Gzip, not gzip, although it's not ambiguous since the reciprocal prefix is nano-, and in general there are no 2^-X0 prefixes that start with g- like there is for Mega-/milli-.
kilometer = 1000 meters