Discuss the shapes of s-orbitals.

For s-orbital, l = 0 and hence m = 0. Thus s-orbital has only one orientation. This means that probability of finding an electron in s-orbital is same in all directions at a given distance from the nucleus. In other words. Is orbital is non-directional and spherically symmetrical.

The s-orbitals of higher energy levels (2s, 3s, etc.) are also non-directional and spherically symmetrical. However, the effective volume or size is larger than Is orbital. Thus 2s-orbital is larger than 1s-orbital. Also in 2s-orbital, there is a spherical shell within the orbital where the probability of finding the electron is practically zero. This is called a node or nodal plane or nodal surface.
In general, the number of nodes in s-orbital of any energy level is equal to (n - 1), where n represents the principal quantum number.