Ah, yes. "He just smiled and gave me a Vegemite sandwich".
It's savoury. Salty. Umami (the fifth basic taste). It has a sharpness to it like tomato paste can have. There's no way you would dip in and eat a spoonful from the jar like peanut butter.
Most people make the mistake of spreading it thick like Nutella and that's deadly. You need hot toast (preferably plain, empty calorie white bread), melted butter and a light scraping of Vegemite over the top.
Bliss.
Comfort food. If you're sick, that's what your mum makes you to ease you back into food.