Oh Lawdy, thank God I'm in that sweet spot -- old enough to have tons of memories but still young enough to remember most of them!
When a wee'un, it was the Good Humor man in those modified Ford pick-up chassis trucks. Used to get something on a wooden pole with vanilla ice cream with a fudge center that you pushed up and which may or may not have had "rocket" in it's name (uh oh, there goes the sweet spot).
It was the baby boom, baby, and that dude in his dorky white uniform and hat that looked like something out of the thirties or forties was serially mobbed in the four block nexus of my suburban "hood". There were literally 30-35 kids within three years either way of my age, plus countless more older and younger than that. It probably took that guy literally far more than a half an hour to do those entire four blocks O Russell St. and Rodgers St., Ridley Park, Pa.
For some reason I have to give a mad shout out for the Creamsiscle -- that heavenly vanilla ice cream wrapped in orange sherbet confection that some previous poster described. Genius! Genius, I say -- even though that was never my choice from the Good Humor man.
As a mid teen, the Good Humor guys faded and it was all Mister Softee in enclosed, heavily modified step vans -- the source of many a juvenile joke. Of course, back further in the day we were all too young to perhaps understand yet appreciate the more "adult" humor surrounding the "Good Humor man".
Edit: From Mister Softee, it was chocolate soft serve covered with jimmies -- or what the rest of you culturally deprived types would call "sprinkles".