(1) The reflecting surface of the concave mirror is bulged inwards. But the reflecting surface of the convex mirror is bulged outwards.
(2) Concave mirror produces real and inverted images (except when the object is placed between pole and focus. When the object is placed between F and P, concave mirror produces virtual and erect image). But the convex mirror always produces virtual and erect images.
(3) The image formed by the concave mirror may be enlarged or diminished, according to the position of the object. The image formed by the convex mirror will be always diminished. Cheers!!