What is a good Tik Tok caption?

I’ve seen some of you here talk about good captions. I have litteraly no idea what you mean by that : is it good hashtags ? How do you even pick good hashtags (I mean I basically know how I’m not retarted but if you got some tips please share them) ? What is a good caption to you ? I’m sorry for all those questions I’m new on Tik Tok