Simple Vim commands you wish you’d known earlier [closed]

I’m learning new commands in Vim all the time, but I’m sure everyone learns something new once in a while. I just recently learned about this:

zz, zt, zb – position cursor at middle, top, or bottom of screen

What are some other useful or elegant commands you wish you’d learned ages ago?

I really wish I’d known that you can use Ctrl+C instead of Esc to switch out of insert mode. That’s been a real productivity boost for me.