writing vs inscription

writing and inscription both are nouns.

Word	Noun	Adjective	Verb	Adverb
writing	Yes	No	No	No
inscription	Yes	No	No	No

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

writing: the activity of putting something in written form
inscription: the activity of inscribing (especially carving or engraving) letters or words

Other hyponyms of writing include coding, cryptography, secret writing, steganography, handwriting, notation.

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

writing: the work of a writer; anything expressed in letters of the alphabet (especially when considered from the point of view of style and effect)
inscription: letters inscribed (especially words engraved or carved) on something

writing (noun)	inscription (noun)
the activity of putting something in written form	the activity of inscribing (especially carving or engraving) letters or words
the act of creating written works	letters inscribed (especially words engraved or carved) on something
the work of a writer; anything expressed in letters of the alphabet (especially when considered from the point of view of style and effect)	a short message (as in a book or musical work or on a photograph) dedicating it to someone or something
letters or symbols that are written or imprinted on a surface to represent the sounds or words of a language
(usually plural) the collected work of an author