Ryan demonstrates the two angular measurement concepts, which are minutes of angle, and mils. Minutes of angle is the older more traditional process. Mils is the newer metric way to setup the angular measurements in your rifle.
Ryan discusses the various effects on your bullet as it is traveling. Gravity has an effect on your bullet. Wind is another key factor to account for in bullet travel. Environmental effects on your bullet matter as well. Chart your data to know how to adjust.
Ryan explains why collecting your DOPE is so important. DOPE stands for Data On Previous Engagements. Using this reference data will help you be more efficient and effective. Dial it in and write it down for future reference.