Nikon SLR cameras have three focusing modes: F, S and C. What are the modes? What is the difference?

C continuous focusing mode

Auto focus mode

Single focus mode of:

For example, if you shoot a person and focus in this way, no matter whether he walks towards you or away from you or the photographer to re-compose, this focus will only maintain the state of success just now. In other words, the previous focusing result is always maintained.

2.c continuous focus mode:

Or for example, if you shoot a person and focus in this way, even if you have finished focusing correctly, you will continue to focus (press the shutter or AF-on key). When he walks towards you or away from you, as long as the focus is on him, the focus will continue. Re-composition will refocus, that is, always focus on the current in-focus position.

3. Automatic gear:

I don't want to talk about it, just pretend it doesn't exist. Because this is what contains two unreliable things together.