Back to plain old "Ordinary" time....or are we?

There is some confusion as to what the term ordinary time means in the Catholic Church. I think I always assumed, and many still do, that it means nothing "extraordinary" is happening. But that's not really accurate. In fact, when the Church calls the period of time "Ordinary", it simply refers to ordinal numerals.

According to Wikipedia:

In linguistics, ordinal numerals or ordinal number words are words representing position or rank in a sequential order; the order may be of size, importance, chronology, and so on (e.g., "third", "tertiary"). They differ from cardinal numerals, which represent quantity (e.g., "three") and other types of numerals.

The other type of numbers are called cardinal numerals which would be used for things like quantities and amounts. So it makes sense that the weeks are numbered in the Church this way.

Today, Monday, January 11, 2021, is called the first day of Ordinary Time. We have begun a new season. Something I cannot seem to explain is that although today is the first day of ordinary time according to the calendar, it also says that this coming Sunday, on January 17, is the "second Sunday of Ordinary Time". Very confusing. If today is the first day of Ordinary time, that would mean yesterday was presumably not included.

In fact, yesterday is the Solemnity of the Baptism of Our Lord. According to the calendar and the archbishop this morning, today is the first day of the liturgical new year, and therefore yesterday would not be included. I am very confused. If anyone knows what is going on, please let me know.

The basic idea behind ordinary time is that there are two major periods in the Christian calendar: Christmas and Easter. We prepare for these two major periods with Advent and Lent, respectively. Ordinary time is basically the period of time outside of these. The longest period of continual Ordinary Time is between the end of Eastertide and the beginning of Advent which in 2021 will be approximately 188 days, depending on how it's supposed to be calculated. In other words, more than half the year.

It's important to note that all Masses are equally important and extraordinary in that sense since the body, blood, soul, and divinity of our Savior comes to us at those times. Also, even during ordinary time, there are major solemnities, feasts, etc.