The Character Families page group characters by similarity. More specifically, they are grouped by how all the sounds are related to avoid mixing up the meanings. For instance, the very first "family" has yi1 and si1 grouped together because they sound similar. This is an alternative way of learning HSK Characters.
A more elaborate explanation is available in the video below.
Now take a picture of any character family page and upload it below:
Congratulations! You are done with the first section of the Tutors Certification Program: Learning FC Features.