What does sorting mean?

• We have a list of elements L = (a1, a2, ..., an)

• We have an order relation ≤

• SORT(L) should produce a permutation (Φ(a1), Φ(a2), ..., Φ(an)) with Φ(a1) ≤ Φ(a2) ≤ ... ≤ Φ(an)