This Python Range lesson is for a beginner. Read the short notes, run each example, then change one name or number and run it again.
range does not build a full list immediately. It produces numbers as you ask for them. list(range(...)) shows them all.
The third argument is the step. A negative step counts down.
Example 1: Start here
range(1, 6) stops at 5.
print(list(range(1, 6))) # print writes this; the quotes are not shown
print(list(range(5, 0, -1)))
Example 2: Stop is excluded
range(1, 5) is 1, 2, 3, 4.
print(list(range(1, 5))) # print writes this; the quotes are not shown
Example 3: A step
The third number is the step, so this prints the even numbers.
print(list(range(0, 10, 2))) # print writes this; the quotes are not shown
Example 4: Count backward
A negative step counts down. The stop is still excluded, so 0 is not included.
print(list(range(3, 0, -1))) # print writes this; the quotes are not shown
range(1, 6) stops at 5.
