Someone please explain temping to me !

Can someone please explain temping and how it works for ttc, and noting ovulation ect? 
I have successfully used cm and cervix position as a natural form of birth control for years. Hubby and I are ttc currently, we got pregnant the first month! However that pregnancy ended in miscariage sadly.  And so I am looking for anything that will aid in the process :) 
Thank you!