The way you configure your gradebook is slightly different depending on whether you are using weighted or natural grading. All grades have weight relative to one another. Some courses use graded assessments that are grouped together to give them a collective weight, while Here's an easy way to tell the difference:
If there are four quizzes in your class, and they are collectively worth a percentage of the total grade, you are weighting your grades. If the weight of each quiz in the course is determined by its point total, you are using natural grading.
The following video further illustrates the difference, and covers how to configure each type of gradebook.