We have another question from the mailbag (comment box, really) and it's a great one! A guest wrote in and asked the difference between a Feast and a Solemnity. In responding in the comment box, we realized that there are much more articulate explanations in an article from "The Catechist." Click here to read their snappy explanation.
Just as a side note, there are times when a particular country, diocese, religious order, etc., has permission to celebrate a certain Memorial or Feast with greater solemnity. In our case, we celebrate the "Feast" of the Visitation, the "Memorial" of St. Francis de Sales, and the "Commemoration" of St. Jane de Chantal as Solemnities. In addition, we celebrate the "Commemoration" of St. Margaret Mary as a Feast. It keeps us (and our chaplains) on our toes!