What does face_encoding do in the example code?

From this example
https://github.com/ageitgey/face_recognition/blob/master/examples/facerec_from_webcam_faster.py
In the example here what does the face_encoding in the for loop do and what will happen if i remove it?
Because it was only stated in that statement and not again in the whole script, so i wanted to know what it does. Just a newbie at programming wanting to learn everything thank you :)

face_names = []
for face_encoding in face_encodings:
# See if the face is a match for the known face(s)
matches = face_recognition.compare_faces(known_face_encodings, face_encoding)
name = "Unknown"

Start with examples/facerec_from_webcam_faster.py and inspect the loop containing face_encoding and compare_faces. Clarify the variable's role in the loop and what behavior changes if that loop variable is removed; the issue is done when the example's control flow is understandable to a beginner.