Hey
@JustGeorge
Thanks for the question!
The answer is that they all follow a basic "format" liturgically speaking,
however the church has a hierarchy of celebrations from saints' memorials, to feasts, to solemnities:
(a) there are these different 'statuses' of saints's feast-days, with some being just memorials (the common form) whereas others are accorded a "feast" proper, that is a higher level of celebration based on the importance or popularity of the individual and a few special cases, such as ones to do with the Blessed Virgin Mary or John the Baptist, are actually solemnities (the holiest of holiest, so to speak, given that Christmas and Easter are both solemnities);
(b) outside of the liturgical context, popular piety and traditions can vary widely, with for example the 'patron' saint of a certain nation being especially celebrated in that one region, with particular customs and traditions
To elaborate some more on the above, most liturgical celebrations of individual saints during the church year are known formally as
memorials.
The ones classified as "
feasts" are reserved for especially venerated events in Christian history and for saints of particular significance, such as the Twelve Apostles or Mary Magdalene.
When Mass is celebrated on St. Mary Magdalene's feast on 22nd July, for example, the standard formula for a daily Mass - which would still be followed on the 'memorial' day of other canonized saints - is not adhered to.
Instead, the Gloria is sung and special intercessory prayers are offered expressly to Mary Magdalene and certain readings are selected from scripture (the lectionary), which are especially pertinent to the saint whose feast it is.
But because St. Patrick, to take another example, is the patron saint of Ireland, his feast-day is actually a
solemnity (even higher status) for the Irish Church, and so on for St. Andrew's Day for Scottish Catholics and St. George's Day for English Catholics, and St. Joan of Arc's feast-day for French Catholics etc. etc.
Now,
outside of the liturgy itself, saint's feast days are celebrated in all manner of ways and with every tradition one could think of by Catholics in different parts of the world.
St. Paddie's Day celebrations are well-known to anyone who is an Irish expat or of Irish heritage: with parades, special foods, music, dancing, raucous drinking and a whole lot of green and shamrocks.
Throughout Latin America, the first three months of the year are devoted to a huge variety of
fiestas patronales, or patron saint festivals, such as the
Fiestas de la Calle San Sebastián, a street party that involves mass gatherings of artists, live music and dance performances.
Saint Walpurgis Night, the feast day of St. Walpurga, an 8th-century abbess, is hugely celebrated through central and northern European countries (Germany, Austria, the Netherlands, Czech Republic etc.) with bonfires, parties, pageants and various local customs, such as the Czech tradition that young women should be kissed past midnight (and during the following day) under a blossoming cherry tree.
And the list goes on and on in different Catholic cultures, where certain national or local saints' cults are particularly emphasized or part of the heritage of the region, such as St. Andrew's Day for a Scottish Catholic like me.
Catholics basically love any old excuse for a party, and so, since you have a saints' memorial, feast or solemnity on every day of the week that's important either universally or particularly in one given place, we have plenty of opportunities
