https://www.theverge.com/2018/6/4/17426092/animoji-update-memoji-announced-apple-wwdc-2018

Apple announced today at WWDC that Animoji is getting updated with tongue detection, new characters, and the ability to create a custom Animoji that looks like you, called Memoji.

Now, where you would normally select Animoji, swipe right and click on the add button to create a custom Memoji. Here you can build a virtual version of you from the ground up, picking things like freckles, skin color, hairstyle, and accessories like glasses and earrings. It can then be saved to use within messages like a regular Animoji, or even overlaid on your own face when taking a selfie for a fun real-world / cartoon hybrid version of yourself.