Interesting Facts About Python strings

Strings are one of the most commonly used data types in Python. They allow us to work with text and can be used in various tasks like processing text, handling input and output and much more. Python strings come with several interesting and useful features that make them unique and versatile.

Here are Some Interesting Facts About Python Strings

1. Strings are Immutable

Once a string is defined, it cannot be changed.

a = 'Geeks'
print(a)

a[2] = 'E'
print(a) 

Output:

Traceback (most recent call last):
  File "/home/adda662df52071c1e472261a1249d4a1.py", line 9, in 
    a[2] = 'E'
TypeError: 'str' object does not support item assignment

But below code works fine.

a = 'Geeks'
print(a)
a = a + 'for'

print(a) 

Geeks
Geeksfor

2. Strings Can Be Concatenated Using the + Operator

We can easily combine (concatenate) strings using the + operator. This simple operation allows you to build longer strings from smaller ones, which is helpful when working with user input or constructing strings dynamically.

first_name = "Krishna"
last_name = "Nand"
full_name = first_name + " " + last_name
print(full_name)  

Krishna Nand

3. Strings Support String Multiplication

In Python, we can repeat a string multiple times using the * operator. String multiplication can be used to create patterns, repeat text, or perform formatting tasks easily.

s = "gfg"
print(s * 3)  

gfggfggfg

4. Strings Can Be Accessed with Indexes

You can access individual characters in a string by using their index. The first character has index 0, and the last character can be accessed with a negative index (-1). This allows you to quickly access and work with specific characters within a string.

s = "GFG"
print(s[0])  
print(s[-1])  

G
G

5. Three ways to create strings

Strings in Python can be created using single quotes or double quotes or a triple quotes. The single quotes and double quotes works same for the string creation. Talking about triple quotes, these are used when we have to write a string in multiple lines and printing as it is without using any escape sequence.

a = 'Geeks'
b = "for"
c = '''Geeks a portal 
for geeks'''

d = '''He said, "I'm fine."'''

print(a)
print(b)
print(c)
print(d)

print(a + b + c) 

Geeks
for
Geeks a portal 
for geeks
He said, "I'm fine."
GeeksforGeeks a portal 
for geeks

6. Printing single quote or double quote on screen

We can do that in the following two ways:

• First one is to use escape character to display the additional quote.
• The second way is by using mix quote, i.e., when we want to print single quote then using double quotes as delimiters and vice-versa.

Example-

print("Hi Mr Geek.")

# use of escape sequence
print("He said, \"Welcome to GeeksforGeeks\"")    

print('Hey so happy to be here')

# use of mix quotes
print ('Getting Geeky, "Loving it"')                

Hi Mr Geek.
He said, "Welcome to GeeksforGeeks"
Hey so happy to be here
Getting Geeky, "Loving it"

7. Printing escape character

If there is a requirement of printing the escape character(\) instead, then if user mention it in a string interpreter will think of it as escape character and will not print it. In order to print the escape character user have to use escape character before '\' as shown in the example.

# Print Escape character
print (" \\ is back slash ")

 \ is back slash 

8. String Comparison is Case-Sensitive

Python string comparisons are case-sensitive. This means that "hello" and "Hello" are considered different strings. This allows for precise string matching, but it’s also important to handle case sensitivity when comparing user input or working with text data.

print("hello" == "Hello")

False

9. Strings Can Be Multiline

You can create multiline strings in Python using triple quotes (""" or '''). Multiline strings are useful for writing longer pieces of text or docstrings for functions and classes.

s = """This is
a multiline
string"""
print(s)

This is
a multiline
string

10. Strings Can Be Reversed

You can reverse a string using slicing with a step of -1. Reversing strings can be helpful in various tasks, such as palindromes or analyzing strings from right to left.

s = "GeeksForGeeks"
print(s[::-1])  

skeeGroFskeeG

Fun Features in Python Strings

1. Strings Can Be Sliced

Python allows you to slice strings, which means you can extract a portion of the string by specifying a range of indices. String slicing makes it easy to extract parts of a string for further processing or analysis.

Example:

s = "hello"
print(s[1:4])  

ell

2. Strings Can Be Split into Lists

The split() method splits a string into a list based on a specified delimiter (by default, it splits by whitespace). Splitting strings is useful for tasks like parsing sentences or processing user input into individual components.

Example:

s = "Geeks For Geeks"
words = s.split()
print(words) 

['Geeks', 'For', 'Geeks']

3. Strings Support String Formatting

Python provides multiple ways to format strings, such as the old % formatting method, str.format() method, and f-strings (available in Python 3.6+). String formatting makes it easier to construct dynamic strings, especially when dealing with variables.

Example:

name = "Alice"
age = 25
print(f"My name is {name} and I am {age} years old.") 

My name is Alice and I am 25 years old.

String built-in Methods

Python strings come with a variety of built-in methods that allow you to manipulate and interact with text in powerful ways. Here’s a list of some commonly used string methods:

1. lower()

Converts all characters in the string to lowercase.

Example:

s = "GEEKS FOR GEEKS"
print(s.lower()) 

geeks for geeks

2. replace(old, new)

Replaces occurrences of a substring (old) with another substring (new).

Example:

s = "Hello World"
print(s.replace("World", "Python")) 

Hello Python

3. find(sub)

Returns the index of the first occurrence of the specified substring (sub). Returns -1 if the substring is not found.

s = "Hello World"
print(s.find("World"))  
print(s.find("Python"))  

6
-1

4. count(sub)

Returns the number of occurrences of the specified substring (sub) in the string.

s = "Geeks For Geeks"
print(s.count("Geeks"))  

2

5. isdigit()

Returns True if all characters in the string are digits.

s = "12345"
print(s.isdigit())  
s = "Hello123"
print(s.isdigit()) 

True
False

Explore in detail about - Python String Methods