The Power of Three -- Gram's Power
How the Halliwell sisters received their powers and what they are.

Prudence "Prue" Halliwell - Her powers are telekinesis and astral projection. She is the oldest of the Halliwell sisters and also the most responsible one in the household. Prue fought against Shax, the Source's assassin but didn't survive.

Piper Halliwell - Her powers are molecular immobilization and then later molecular combustion. She was the middle sister until Prue's death. This made her the oldest sister and she had to look after her sisters just like Prue did.

Phoebe Halliwell - Her powers are passive. They are premonitions and then later empathy. To aid with the power of three, she has a knack for writing really good spells and she has martial arts abilities which help her fight demons and defend herself and her sisters.

Paige Matthews - She is the youngest half-sister of the Halliwells through her birth mother. Her birth father was a Whitelighter. This gave Paige the ability to orb along with her witch powers, similar to Prue's, except she has to call out the object to telekinetically move it over to her.