Since others had answered the abbreviation bit of the question, Nia turned her attention to the other part. She'd seen it done on television, and whilst wouldn't know how to do it properly, had a fair idea. She raised her hand.

"There are two parts to perform, aren't there?" she started to answer. "You press up and down on the ribs over the heart, kinda to manual pump it so the blood keeps moving round. That's known as compressions, I think. And you also put air into the person's lungs, so oxygen still goes to the vital organs." She looked thoughtful. "It won't revive a person, if I remember rightly, but keeps them going til someone arrives who can? "