"Yes," Hermione agrees, looking a bit embarrassed- yes, she can go from blasting holes in things to sheepish in seconds. It's a skill. "But most people will use to to remove obstacles in their path rather than people. The biggest thing to watch out for is not to get hit by any debris. There are more specific spells that people will actually aim at opponents- probably the most common is a Stunning Spell. Just knocks people out if you're doing it right, and it's painless- though taking too many in quick succession can be dangerous to the heart, that's usually only if you have a pre-existing condition, or if you're elderly or especially young or pregnant- you know. The sort of things you can't go on rollercoasters with."

She gives her another half smile. "It's distinctive, luckily. You'll see a jet of red light, so that's just a matter of dodging, and the incantation's Stupefy, though it's usually one of the first things people learn to do non-verbally because it's so useful."