Why is Google's best image model called "Nano Banana"? And why are you using the wrong one?

This is a submission for the Google I/O 2026 Writing Challenge

Google now has six image models (one is called "Nano Banana"). Here's which to actually use.

Everyone covering Google I/O 2026 is writing about agents, Antigravity, and whether AI is coming for our jobs. Meanwhile, I opened AI Studio, clicked into image generation, and found a quietly hilarious situation: six different image models, two completely different families, prices ranging nearly 7×, and one of them is officially named "Nano Banana."

Nobody's written the guide for this. So here it is — the two families, what each is for, and the price-vs-quality call, in plain terms.

Two families, two totally different jobs