Good news: Today's grammar point is mega-useful.
Bad news: There is no simple equivalent in English.
Unrelated news: I've really been craving popcorn lately.

Suddenly, a question:

A:
アクロヨガって何ですか。
アクロヨガ　って　なん　ですか。
What’s Acroyoga?
Literally: “Acroyoga + って + what + ですか.”

The ideal answer to this question would be to grab Person A and lift him/her up in the air, like this:

The second best option might be to answer with:

B:
ペアで行うヨガのことです。
ペア　で　おこなう　ヨガ　の　こと　です。
It’s a type of yoga done in pairs.
Literally: “pair + で + carry out + yoga + の + thing + です.”

I'm not sure if "pair" is the best word, since I think some Acroyoga poses are done with three people. But then, I've never tried it, so don't ask me.

Wait a sec. I think we just passed our grammar point.

JLPT N3: って (topic marker)

The people writing the JLPT must have no friends because they really don't give much love to everyday, spoken Japanese.

I say this because I think this usage of って deserves to show up on JLPT N4 or N5.

I use it EVERY DAY!

So what does (this) って mean?

The short version: It means ～とは or ～というのは.

The slightly longer version: It marks a word to be defined or explained.

We saw:

アクロヨガって何ですか。
アクロヨガ　って　なん　ですか。
What’s Acroyoga?
Literally: “Acroyoga + って + what + ですか.”

The thing we want to be defined or explained, in this case Acroyoga, comes right before って.

I'm always using って to get people to clarify words and concepts that I'm not familiar with.

For example, imagine that your friend randomly says:

最近アクロヨガやってるんだ。
さいきん　アクロヨガ　やってる　んだ。
Lately I've been doing Acroyoga.
Literally: "recently + Acroyoga + am doing + んだ."

You have no idea what Acroyoga is, so you ask:

アクロヨガって？
アクロヨガ　って？
What's Acroyoga?
Literally: "Acroyoga + って?"

The whole sentence would actually include the word 何 (なに), but we can leave it out:

アクロヨガって何？
アクロヨガ　って　なに？
What's Acroyoga?
Literally: "Acroyoga + って + what?"

It may help to think of って as a "spoken quotation marker" and that it is putting the word before it into quotations in order to identify it as the thing that will be defined or explained.

Another conversation:

A:
あの時は大変でしたね。
あの　とき　は　たいへん　でした　ね。
That was a difficult time, wasn’t it?
Literally: “that + time + は + tough + was + ね.”

B:
あの時っていつのことですか。
あの　とき　って　いつ　の　こと　ですか。
What time are you referring to?
Literally: “that + time + って + when + の + thing + ですか.”

A:
先週の飲み会のことです。
せんしゅう　の　のみかい　の　こと　です。
The drinking party last week.
Literally: “last week + の + drinking party + の + thing + です.”

Person B wants Person A to clarify what they mean by あの時, so they stick a って onto the end of it, and then ask "when の thing?"

A more literal translation of the sentence might have been:

あの時っていつのことですか。
あの　とき　って　いつ　の　こと　ですか。
When is "that time" (referring to)?
Literally: “that + time + って + when + の + thing + ですか.”

A:
車を運転するのって、難しいですか。
くるま　を　うんてん　する　の　って、　むずかしい　ですか。
Is driving a car difficult?
Literally: “car + を + driving + do + の + って, + difficult + ですか.”

B:
慣れれば簡単ですよ。
なれれば　かんたん　です　よ。
It’s easy once you get used to it.
Literally: “if (you) get used to (it) + easy + ですよ.”

First, let's note that the の coming after 運転する, "to drive" is making it into a noun. So we can thinking of 運転するの as "driving" or "the act of driving." In other words, の has made the words before it into a noun phrase. We see this usage of の in many of our lessons.

The thing that will be explained or defined is "the act of driving a car," so Person A sticks a って onto it, then asks if it's hard.

I kind of wish that we talked like this in English, and we could just make quotation gestures with our hands to mark quotes:

"Driving a car," difficult?

Who ever said Japanese didn't make sense?

One last example, then you're on your own:

A:
田舎に住むのって、どんな感じですか。
いなか　に　すむ　の　って、　どんな　かんじ　ですか。
What’s it like living in the countryside?
Literally: “countryside + に + live + の + って, + what kind of + feeling + ですか.”

B:
不便だけど、楽しいですよ。
ふべん　だけど、　たのしい　です　よ。
It’s inconvenient, but also fun.
Literally: “inconvenient + だ + けど (=but), + fun + ですよ.”

When I was just getting started with Japanese, I was very confused by things like って, which I simply could not conceptualize with my 99.999% English-speaking brain.

It simply didn't make sense to me when I read explanations. I mean, the English translations seem to be completely ignoring the existence of って！

But, in time, I got used to って and other elusive grammar points. And now I don't even notice myself using it (which I do a lot).

Keep an eye out for this one. It's very common in spoken language. The books will tell you it's used in "informal" or "casual" language, but I think you're pretty much always safe using this one... unless you're working in customer service or something, I guess.

Oh, and maybe avoid using it in formal written Japanese. But feel free to use it when texting your crush.