The overlapping of two s atomic orbitals produces two molecular orbitals, one bonding molecular orbital and one anti-bonding molecular orbital.
Whenever two atomic orbitals overlap according to molecular orbital theory, it will produce one bonding and one anti bonding molecular orbital. Molecular orbital theory is also a way for determining molecular shape wherein electrons are not assigned to character bonds between atoms, however are dealt with as transferring underneath the effect of the nuclei within the entire molecule.