in the 3 and 4 lines why he took "c" and what does it mean? anyone plz

Question

The next part of the program finds what percentage of the text each character of the alphabet occupies.

def count_char(text, char):
count = 0
for c in text:
if c == char:
count += 1
return count

filename = input("Enter a filename: ")
with open(filename) as f:
text = f.read()

for char in "abcdefghijklmnopqrstuvwxyz":
perc = 100 * count_char(text, char) / len(text)
print("{0} - {1}%".format(char, round(perc, 2)))

Answer 1

basically they name the parameter 'c' lol like
def some_function(x):
there im naming my parameter x
same thing goes to for, i can actually do for my_parameter in text: but they chose c because its short so yeah