What do I and n stand for in python?

So there was a different question about this, my confusion lies in, can you use any letter to mean i or n? Does it have to be the letters i, and n? or can it be t and q? or anything.

Example (say i defined the range… I’m still a early beginner)

for i in range(10)


for q in range(10)

Are they the same thing?