It can be used in various contexts:
* To describe something belonging to your mother: "C'est le livre de ma mère" (This is my mother's book).
* To indicate the origin of something: "J'ai reçu une lettre de ma mère" (I received a letter from my mother).
* In a figurative sense: "Elle a la beauté de ma mère" (She has the beauty of my mother).
The exact meaning will depend on the context in which it's used.