there is a huge difference between them. Modern judo is largely sport, while if you choose classical jujutsu it is more of a martial art in the full sense of the word. they both have the same roots, but are very different today.
there are techniques that exist in both, and sometimes the overlap may seem quite large, but the intention is different. in judo, they are used to score points. in jujutsu, they are used to hurt. that is why strikes are VERBOTEN in judo, because they are too dangerous for sport.
not taking away from judo at all! its great, and builds great exponents. but it is still a combat sport in which you score points. jujutsu is a martial art.
Practice does not make perfect.
practice makes perfect.