Newbie question - do I need to water boil jam and/or pickles?

Hi all, sorry for the basic question! My recipe book for jam and pickles say to pack into a sterile jar, seal and store - they don't say if I should can them to seal or not. I've been running them through the water bath as a just-to-be-sure but is that going to ruin the flavour? A friend says she never water baths her jams, but another says he does everything. What's the right answer?!