What is a String in Python?
In Python, a string is a sequence of characters enclosed within single quotes ('), double quotes ("), or triple quotes (''' or """).
Example:
string1 = 'Hello'
string2 = "World"
string3 = '''Python'''
string4 = """Programming"""
Types of String Formats in Python
Python provides various ways to format and manipulate strings:
1. String Concatenation
Joining multiple strings using the + operator.
name = "Alice"
greeting = "Hello, " + name + "!"
print(greeting) # Output: Hello, Alice!
2. String Formatting Methods
a) Using % Formatting (Old Method)
This method is similar to C-style string formatting.
name = "Alice"
age = 25
print("Hello, %s! You are %d years old." % (name, age))
%s→ String%d→ Integer%f→ Float
b) Using .format() Method
Introduced in Python 3, it allows inserting values in placeholders {}.
name = "Bob"
age = 30
print("Hello, {}! You are {} years old.".format(name, age))
You can also specify index positions:
print("Hello, {1}! You are {0} years old.".format(age, name))
c) Using f-Strings (Python 3.6+)
f-Strings (formatted string literals) are the most efficient way to format strings.
name = "Charlie"
age = 22
print(f"Hello, {name}! You are {age} years old.")
They support expressions inside {}:
num1, num2 = 10, 20
print(f"Sum of {num1} and {num2} is {num1 + num2}.")
3. Multi-line Strings
Using triple quotes (''' or """) for multi-line strings.
message = """Hello,
This is a multi-line string.
It spans multiple lines."""
print(message)
4. Raw Strings (r'' or r"")
Used to prevent escape characters (\n, \t, etc.) from being interpreted.
path = r"C:\Users\Alice\Documents\file.txt"
print(path) # Output: C:\Users\Alice\Documents\file.txt
5. Byte Strings (b'')
Used for handling binary data.
byte_str = b"Hello"
print(byte_str) # Output: b'Hello'
6. Unicode Strings
Python 3 strings are Unicode by default, but you can explicitly define them:
unicode_str = u"Hello, Unicode!"
print(unicode_str)
7. Escape Sequences in Strings
Escape sequences allow inserting special characters:
new_line = "Hello\nWorld" # New line
tab_space = "Hello\tWorld" # Tab space
quote_inside = "She said, \"Python is great!\"" # Double quotes inside string
8. String Methods
Python provides several built-in string methods:
s = " hello Python "
print(s.upper()) # ' HELLO PYTHON '
print(s.lower()) # ' hello python '
print(s.strip()) # 'hello Python' (removes spaces)
print(s.replace("Python", "World")) # ' hello World '
print(s.split()) # ['hello', 'Python']
Conclusion
Python provides multiple ways to handle and format strings, from basic concatenation to f-strings and .format(). f-Strings (f"") are generally the most recommended due to their efficiency and readability.
