In Python, a string is a sequence of characters enclosed in single quotes (‘ ‘) or double quotes (” “).
Note: Strings are immutable means once created, they cannot be changed.
Q: What is the use of a String?
Ans: String is used to represent text.
Note:- strings are sequences of one-character strings.
Q: How to create a String in Python?
Ans: You can create a string by assigning a sequence of characters to a variable.
# Single quotes
name = 'John'
# Double quotes
greeting = "Hello, world!"
Multiline Strings
To create a multiline string, you can use triple quotes (‘ ‘ ‘or”””):
multiline_string = '''This is
a multiline
string.'''
String Indexing and Slicing
Indexing allows you to access individual characters in a string, using a zero-based index. Negative indexing starts from the end.
Slicing allows you to extract a part of the string by specifying a range.
text = "Python"
print(text[0]) # Output: 'P' (first character)
print(text[-1]) # Output: 'n' (last character)
print(text[1:4]) # Output: 'yth' (characters from index 1 to 3)
Common String Methods
Python provides some common methods below:
lower(): It is used to convert the string to lowercase.
upper(): It is used to convert the string to uppercase.
strip(): It is used to remove leading and trailing spaces.
replace(old, new): It is used to replace occurrences of a substring.
split(delimiter): It is used to split the string into a list of substrings.
join(iterable): It is used to join elements of an iterable (like a list) into a single string.
text = " Hello, Python! "
print(text.lower()) # Output: " hello, python! "
print(text.upper()) # Output: " HELLO, PYTHON! "
print(text.strip()) # Output: "Hello, Python!"
print(text.replace("Python", "World")) # Output: " Hello, World! "
String Concatenation
You can concatenate strings using the + operator or join multiple strings with spaces using join().
first_name = "John"
last_name = "Taylor"
full_name = first_name + " " + last_name # Concatenation
print(full_name) # Output: "John Taylor"
String Formatting
You can insert variables into strings using several methods:
1. F-strings (Python 3.6+):
name = "John"
age = 35
print(f"My name is {name} and I am {age} years old.")
2. format() method:
print("My name is {} and I am {} years old.".format(name, age))
3. Percent (%) formatting:
print("My name is %s and I am %d years old." % (name, age))
Python String – Questions and Answers
Q 1: What is a string in Python?
Ans: A string is a sequence of characters enclosed in quotes.
Q 2: How do you create a string?
Ans: By using single, double, or triple quotes.
Q 3: Are strings mutable in Python?
Ans: No, Python strings are immutable.
Q 4: How do you access string characters?
Ans: By using indexing, starting from index 0.
Q 5: Can strings be concatenated?
Ans: Yes, strings can be joined using the + operator.
Python String – Objective Questions (MCQs)
Q1. Which of the following is the correct way to create a string in Python?
Q2. What will be the output of the following code?
x = "Python"
print(x[0])
Q3. Which of the following operators is used to concatenate two strings in Python?
Q4. What will be the output of the following code?
x = "Hello World"
print(x.lower())
Q5. Which of the following statements about strings in Python is true?