1. For Loops

for loops are used to iterate over a sequence (like a list, tuple, or string). Each time through the loop, a variable takes on the value of the next item in the sequence.

nums = [1, 2, 3, 4, 5]
for num in nums:
    print(num)
   

Output:

1
2
3
4
5
   

2. Break and Continue Keywords

break and continue are used to control the flow within a loop.

• break immediately exits the loop.
• continue skips the rest of the current iteration and moves to the next.

Break Example:

nums = [1, 2, 3, 4, 5]
for num in nums:
    if num == 3:
        print("Found it!")
        break
    print(num)
   

Output:

1
2
Found it!
   

Continue Example:

nums = [1, 2, 3, 4, 5]
for num in nums:
    if num == 3:
        print("Found it!")
        continue
    print(num)
   

Output:

1
2
Found it!
4
5
   

3. Nested Loops

Nested loops occur when one loop is placed inside another. The inner loop executes completely for each iteration of the outer loop.

nums = [1, 2, 3, 4, 5]
for num in nums:
    for letter in 'abc':
        print(num, letter)
   

Output:

1 a
1 b
1 c
2 a
2 b
2 c
3 a
3 b
3 c
4 a
4 b
4 c
5 a
5 b
5 c
   

4. Range Function

The range() function is useful for iterating a specific number of times.

for i in range(10):
    print(i)
   

Output:

0
1
2
3
4
5
6
7
8
9
   

You can also specify a start and end value:

for i in range(1, 11):
    print(i)
   

Output:

1
2
3
4
5
6
7
8
9
10
   

5. While Loops

while loops continue to execute as long as a specified condition is true.

x = 0
while x < 10:
    print(x)
    x += 1
   

Output:

0
1
2
3
4
5
6
7
8
9
   

While Loop with Break:

x = 0
while x < 10:
    print(x)
    if x == 5:
        break
    x += 1
   

Output:

0
1
2
3
4
5
   

Infinite While Loop (with Break):

x = 0
while True:
    print(x)
    if x == 5:
        break
    x += 1
   

Output:

0
1
2
3
4
5
   

Caution: Ensure your while True loops have a break condition to avoid infinite loops.