coding vs decoding

coding and decoding both are nouns.

Word	Noun	Adjective	Verb	Adverb
coding	Yes	No	No	No
decoding	Yes	No	No	No

As nouns, decoding is a hyponym of coding; that is, decoding is a word with a more specific, narrower meaning than coding:

coding: act of writing in code or cipher
decoding: the activity of making clear or converting from code into plain text

Other hyponyms of coding include encoding, encryption, recoding, decipherment, decryption.

coding (noun)	decoding (noun)
act of writing in code or cipher	the activity of making clear or converting from code into plain text