While cats might purr for various reasons, a deep and constant purr while they're nestled up to you or on your lap is often a sign of contentment and love.
A cat that nudges or pushes its head against you is marking you with scent glands located on their head. This behavior, called "head bunting," signifies that they consider you part of their family or "clan."
Cats may knead with their paws on your lap or beside you. This behavior originates from kittenhood when they kneaded their mother's belly to stimulate milk flow. As adults, cats often knead when they're feeling particularly relaxed and loved.
Whether it's a toy, dead insect, or even a mouse, when a cat brings you a "gift," it's often a sign of affection and trust.
A cat that approaches you with its tail held high, especially with a little curve at the tip, is signaling happiness and affection.