There are four kinds of electron configurations: s, p, d, and f orbitals. S orbitals are roughly sphere-shaped, p orbitals are shaped like a dumbbell, d orbitals are usually shaped like a four-leaf clover, and f orbitals form a mathematically complex shape. An atom can have more than one orbital; in fact, all except hydrogen do. Similarly, atoms can have more than one of each kind of orbital.