What is a set? What is a repetition? How do sets and repetitions relate to one another in the context of a workout?

a repetition is one complete exercise, e.g., pull-up, push-up, etc.

a set is a certain number of repetitions.
a workout is a number of sets of different kinds, developing various muscle groups.

Sets and repetitions are closely related in a workout. Sets help to organize the number of repetitions performed for a given exercise. For example, if an individual is performing push-ups, they may aim to do three sets of ten repetitions each. This means they will perform ten push-ups, rest, repeat for a total of three sets.

The number of repetitions and sets performed can vary depending on the individual's fitness goals and the type of exercise being done. Ideally, as an individual progresses in their workouts, they may aim to increase the number of repetitions per set, or add more sets to challenge themselves and continue building strength and endurance.