As 2017 makes its departure and we prepare to flip the calendar into 2018, it's important to look back and reflect on the year that was.

What did we learn? What can we expect for 2018?

Well, in the span of 365 days, we learned quite a lot in the world of international swimming. But, to simplify, here are our three biggest takeaways from the sport as a whole in 2017.

1.) Caeleb Dressel is really, really good

Half-man, half-gator Caeleb Dressel took the world by storm in 2017 by picking up seven — yes, seven — gold medals at the FINA World Championships in July. Almost as impressive as the feat itself is the manner in which he performed it.

July 29, 2017 — a day that will forever be immortalized. Dressel treated this day like it was a college dual meet in Gainesville, Florida. Only it wasn't. It was day seven at Worlds in Budapest, Hungary, where he put on a spectacular performance for the ages.

Race No. 1 — 50m Freestyle — Dressel claimed gold in 21.15, a new American record and a time that places him as the third-fastest performer of all time.

Race No. 2 — 100m Butterfly — Approximately 30 minutes after his 50m free, Dressel stepped it up a notch with a 49.86 in the 100m fly — the second-fastest performance of all time and only 0.04 off Michael Phelps' 2009 world record.

Race No. 3 — Mixed 4x100m Free Relay — His third and final race of the night, Dressel uncorked a 47.22 to lead off this relay (which, by the way, broke the world record) — just 0.05 off the 47.17 American record he set earlier in the week.

Now, we all knew Dressel was good — great, even. After all, he made the 2016 Olympic team and picked up a gold in the 4x100m freestyle relay. He also solidified himself as the best in the SCY pool with his performances at the 2017 NCAA Championships. 

But what he did in Budapest wasn't good or great. It was legendary. He executed race after race with laser precision and a singular focus. He knew exactly what he needed to do to advance through the heats and semifinals. He was truly a professional and he is truly the best male swimmer in the world right now.

2.) Even when she's not, Katie Ledecky is still great

Have we become numb to Katie Ledecky's greatness?

Ledecky has shown us time and time again that she is capable of swimming fast anytime and anywhere, which is why the swimming community has seemingly placed this absurd expectation on her that she has to break a world record every time she jumps in the water.

Exhibit A: Ledecky takes silver in the 200m free in Budapest behind Italy's Federica Pellegrini — who, by the way, has medaled in this event at every World Championships since 2005. The swimming community immediately begins asking questions such as "what's wrong with Ledecky?" and "has she lost her edge?" Give me a break.

Exhibit B: Ledecky does not break any individual world records at a major international event (World Championships, Olympics, Pan Pacs) for the first time since 2012. The swimming community, again, begins saying things like "she shouldn't have gone to college" and "maybe training at Stanford just isn't working out for her." Again, give me a break.

Even in a time when Ledecky isn't the best she has ever been — which is also better than anyone has ever been — she is still great.

If Ledecky decided to retire from swimming today, she would still be great.

So let's all take a step back, appreciate what we are witnessing, and respect the fact that even the greatest athletes of all time — in any sport — do not perform at their absolute peak 100 percent of the time.

3.) Old dogs can learn new tricks

Disclaimer: age is relative. Thirty is NOT actually old, just relatively old for swimmers

At the 2017 FINA World Championships, a whopping 17 medals were won by swimmers 28 years of age or older (37-year-old Brazilian Nicholas Santos was the oldest medalist with silver in the 50m fly).

By comparison, only three medals were won by swimmers 28 years of age or older at the 2001 FINA World Championships in Fukuoka, Japan.

What does that tell you? Swimmers are finding new ways to stay in the sport and unique methods to continue training at an elite level.

Just look at the podium for the men's 50m backstroke: Camille LaCourt (32), Junya Koga (30), Matt Grevers (32).

You might say, "But that's only a 50." OK, in Budapest alone — Federica Pellegrini won gold in the 200m free at 29, Katinka Hosszu won gold in the 200m/400m IM at 28, David Verasszto took silver in the 400m IM at 28, and Laszlo Cseh took silver in the 200m fly at 31. Those are just a few examples.

At the end of the day, 28-year-old Bruno Fratus — silver medalist in the 50m free in Budapest — said it best, "As long as you are happy and healthy... why not?" 

Sure, there comes a point in time when the body can no longer meet the demands being placed on it. An athlete is unlikely to perform at his or her peak at age 52 compared to age 22. But, who is to judge and put qualifiers on what is deemed "old" and "not old" in sport? Likely someone sitting in the stands.

Looking ahead to 2018...

It's scary to think we are coming up on the halfway point of the quad leading into the 2020 Olympic Games in Tokyo.

So, what is happening and what is at stake? The three biggest international competitions of the year are:

2018 Commonwealth Games

April 4-9

Gold Coast, Queensland, Australia

2018 European Championships

August 3-9

Glasgow, Scotland 

2018 Pan Pacific Championships

August 9-12

Tokyo

With the world splitting apart coming into the halfway point of the quad, many elite swimmers have various focuses.

But as we inch closer to all reconvening in Gwangju, South Korea, for the 2019 FINA World Championships, there are sure to be plenty of storylines.

Stay tuned.