California considers traffic infractions criminal in nature however, several states consider traffic infractions as civil violations. The rules between criminal and civil actions differ greatly so you can't include "all states" when you refer to how they handle traffic citations.
What do you think will happen if, in California, you refuse to sign the citation? [HINT: see CVC 40302(b)] The Notice to Appear is simply releasing you on your own recognizance with your promise to appear at a later date.

