and they are n,l,m_l,m_sn,l,ml,ms. Each specifies a different meaning and its function.
nn is the principal quantum number and states the energy level of an electron. You can think of it as the electron shell number. It can only be a whole number greater than 0, i.e. n>0,AAninZZ.
l is the angular momentum number and specifies the subshell (s,p,d,f,...) of an atom. It therefore determines the shape of the orbital. The conditions are such that l=0,1,2,3,4,...,(n-1).
m_l is the magnetic angular momentum number, and determines the number of orbitals in the subshell. The conditions are such that m_l=-l,(-l+1),(-l+2),...,-2,-1,0,1,2,...,(l-2),(l-1),l.
m_s is the electron spin number and states the direction spin of an electron. It only has two values and does not depend on another quantum number. Conditions are that m_s=+-1/2. Positive 1/2 means an uarr spin while negative 1/2 designates a darr spin.
