Cats have vertical slit pupils that dilate to show mood. Wide eyes signal surprise, narrow eyes show aggression. Slow blinking conveys trust and affection.
Ears facing forward show interest. Flattened ears back signal fear or aggression. Ears swiveling signals detection of a sound.
Upright tail is happy, relaxed. Thumping tail shows agitation. Puffed tail is fearful. Straight up is a friendly greeting.
Whiskers forward signals curiosity. Whiskers back conveys caution or uncertainty. Watch whisker position changes.
Short meows are friendly hellos. Long meows signal distress or need. Muted meows show contentment. Yowling is exaggerated requesting.
Purring conveys contentment and comfort but can also signal distress. Context of purring determines meaning.
Hissing indicates fear, usually accompanied by flattened ears, arched back, and puffed fur. It's a defensive warning.