sketch vs summary

sketch and summary both are nouns.

Word	Noun	Adjective	Verb	Adverb
sketch	Yes	No	Yes	No
summary	Yes	Yes	No	No

As nouns, summary is a hypernym of sketch; that is, summary is a word with a broader meaning than sketch:

Other hypernyms of sketch include sum-up.

sketch (noun)	summary (noun)
preliminary drawing for later elaboration	a brief statement that presents the main points in a concise form
short descriptive summary (of events)
a humorous or satirical drawing published in a newspaper or magazine
a brief literary description

sketch (adjective)	summary (adjective)
	briefly giving the gist of something
	performed speedily and without formality

sketch (verb)	summary (verb)
describe roughly or briefly or give the main points or summary of
make a sketch of