For most users the Pi 3 is the best. It is the fastest with WiFi and Bluetooth and provides the best out of box experience. The Pi Zero requires adapters, is much slower and needs some work and pretty much everything else you can ignore unless you specifically need it.
There are 10 types of people: those who understand binary and those who don't.
What are your "Needs" ? What do you plan to do with it? If you don't know and are unsure, I'm with the others, get a 3B so you can cover most of the bases. I say "most" because the 3B isn't the best choice for embedded projects. Good for just about everything else though.