Male cardinals are brilliant red all over, with a reddish bill and black face immediately around the bill. Females are pale brown overall with warm reddish tinges in the wings, tail, and crest. They have the same black face and red-orange bill.
Northern Cardinals tend to sit low in shrubs and trees or forage on or near the ground, often in pairs. They are common at bird feeders but may be inconspicuous away from them, at least until you learn their loud, metallic chip note.