what does 'rb' mean in csv files? [duplicate]

Question

import csv
with open('test.csv','rb') as file:
    rows = csv.reader(file, 
                      delimiter = ',', 
                      quotechar = '"')
    data = [data for data in rows]

This was in Python: reading in a csv file and saving columns as variables. I couldn't comment, but I'm really confused. What does 'rb' mean?

Answer 1

It means: Read the file in Binary mode.

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