Answer:
Jellyfish and fish have major anatomical differences.
Explanation: Yes, they both swim, but what is truly the difference? Jellyfish have tentacles, whereas fish have fins. Additionally, jellyfish can STING with their tentacles and fish are pretty much harmless to people and other organisms. Also, a jellyfish's swimming pattern is significantly different than a fish's. Biologically, jellyfish and fish are not grouped in the same kingdom, as fish is named "Animalia Chordata", and jellyfish are named "Animalia Linnaeus". Hope that helps :)