In what way is the electronic configuration of transition elements different from that of the non-transition elements?

Transition elements contain incompletely filled d-subshell, i.e., their electronic configuration is (n – 1)d^1–10 ns^0–2  whereas non-transition elements have no d-subshell or their d-subshell is completely filled and have ns^1–2 or  ns² p^1–6 in their outermost shell.