The link below is to an outstanding article on triggers by Steve Jenkins at Real Gun Reviews. It specifically discusses “handgun triggers” and we know sporting rifle triggers do not come in double action, DA/SA etc. None-the-less, the premise and definitions of all the elements (take-up, creep, break, overtravel, etc.) is applicable to rifles. We’ve yet to find better information anywhere on this subject and should answer all your questions and solve the mystery of triggers. Enjoy!
https://www.realgunreviews.com/trigger-definitions-take-up-creep-break-overtravel-reset/