Python Programming for Beginners – Day 6

Loops in Python

In the previous lesson, we learned about Conditional Statements and how programs make decisions using "if", "else", and "elif". Today, we will learn about Loops, which are used to repeat a block of code multiple times.

Loops are important because they help programmers avoid writing repetitive code and make programs more efficient.

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What are Loops?

Loops are used to execute a block of code repeatedly until a condition is met.

Python mainly provides:

• "for" loop
• "while" loop

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The for Loop

A "for" loop is used to iterate over a sequence such as:

• Lists
• Strings
• Tuples
• Ranges

Syntax

for variable in sequence:
    # code to execute

Example

for i in range(5):
    print(i)

Output

0
1
2
3
4

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Understanding range()

The "range()" function generates a sequence of numbers.

Example

for number in range(1, 6):
    print(number)

Output

1
2
3
4
5

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Looping Through a String

Example

word = "Python"

for letter in word:
    print(letter)

Output

P
y
t
h
o
n

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Looping Through a List

Example

languages = ["Python", "Java", "C++"]

for language in languages:
    print(language)

Output

Python
Java
C++

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The while Loop

A "while" loop executes as long as the condition remains "True".

Syntax

while condition:
    # code to execute

Example

count = 1

while count <= 5:
    print(count)
    count += 1

Output

1
2
3
4
5

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Infinite Loops

An Infinite Loop happens when the condition never becomes "False".

Example

while True:
    print("Python")

This loop will continue forever unless stopped manually.

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break Statement

The "break" statement is used to stop a loop immediately.

Example

for i in range(1, 10):
    if i == 5:
        break

    print(i)

Output

1
2
3
4

The continue Statement

​The continue statement is used to skip the current iteration and move to the next. It does not stop the entire loop, only the code following it inside the loop for that specific cycle.

​Example:

for item in ["Apple", "Banana", "STOP", "Cherry"]:
    if item == "STOP":
        continue  # Skip this item
    print(item)

output

Apple
Banana
Cherry

Nested Loops

​A loop inside another loop is called a nested loop. The inner loop executes completely for each iteration of the outer loop. This is useful for working with multi-dimensional data like matrices.

​Example:

adj = ["red", "big"]
fruits = ["apple", "banana"]

for x in adj:
    for y in fruits:
        print(x, y)

output

red apple
red banana
big banana

Conclusion

​Congratulations on finishing Day 6! Today, we learned:

​Loops are essential for automation, repetition, and efficiency.

​The for loop is best for iterating over sequences (lists, ranges, strings).

​The while loop runs as long as a specified condition is true.

​break terminates the entire loop immediately.

​continue skips only the current iteration.

​Mastering loops will significantly improve your ability to handle repetitive tasks and complex data. Great work so far!