My child does things that are physically troubling to those around—throwing objects, grabbing others' things or food, kicking, hitting, biting, pinching.

Hitting, biting, and throwing are often expressions of a request, discomfort, or excitement that can't be put into words. On the spot, first ensure safety (put distance between them and the other person), say briefly "that hurts, let's stop," and skip the long lecture. Once calm, practice one alternative that gets through, like "share" or "no." Recording when and where it tends to happen and reducing triggers—hunger, fatigue, crowds—works as prevention. If it grows in frequency or intensity, or leads to injury, consult a professional with specific situations.