Q.Consider the following string myAddress: myAddress = "WZ-1,New Ganga Nagar,New Delhi" What will be the output of following string operations : i. print(myAddress.lower())
ii. print(myAddress.upper())
iii. print(myAddress.count('New'))
iv. print(myAddress.find('New'))
v. print(myAddress.rfind('New'))
vi. print(myAddress.split(','))
vii. print(myAddress.split(' '))
viii. print(myAddress.replace('New','Old'))
ix. print(myAddress.partition(','))
x. print(myAddress.index('Agra'))

String Methods — What They Are and Why They Exist

Imagine you have a piece of text stored in a variable — a name, a sentence, a paragraph. In most programming languages, that text is called a string. Now, you often need to do things with it: check if it contains a certain word, change it to uppercase, remove extra spaces, split it into a list of words, and so on.

You could write all that logic yourself, looping over each character. But that would be tedious and error-prone. Instead, the language gives you ready-made tools — methods — that live on the string itself. You call them by putting a dot after the string (or the variable holding it), then the method name, then parentheses.

The Precise Statement

A string method is a function attached to every string value that performs a common operation on that string and returns a result (often a new string, a number, a boolean, or a list). The original string is never modified — strings are immutable in most languages (Python, Java, JavaScript, C#). The method returns a new value based on the original.

The Most Common String Methods (with intuition)

Let’s use Python syntax, but the ideas are universal.

1. Changing Case

name = "hello world"
print(name.upper())   # "HELLO WORLD"
print(name.lower())   # "hello world"
print(name.title())   # "Hello World"

Intuition: You have a name that needs to be displayed in all caps for a heading, or all lowercase for a case-insensitive comparison. These methods do exactly that — they return a new string with the case transformed.

2. Checking Content

sentence = "The quick brown fox"
print(sentence.startswith("The"))   # True
print(sentence.endswith("fox"))     # True
print("quick" in sentence)          # True (this is an operator, not a method)
print(sentence.find("brown"))       # 10 (index where "brown" starts)

Intuition: You want to know if a string begins with a certain prefix (like checking if a filename ends with .pdf), or find where a word appears. startswith and endswith return True/False. find returns the index (position) of the first occurrence, or -1 if not found.

3. Removing Whitespace

user_input = "   hello   "
print(user_input.strip())    # "hello"
print(user_input.lstrip())   # "hello   "
print(user_input.rstrip())   # "   hello"

Intuition: When a user types something, they might accidentally add spaces at the beginning or end. strip() removes them from both sides. lstrip removes only left, rstrip only right. This is crucial for cleaning input before comparing or storing.

4. Splitting and Joining

data = "apple,banana,grape"
fruits = data.split(",")      # ["apple", "banana", "grape"]
print(fruits)

new_string = " - ".join(fruits)   # "apple - banana - grape"

Intuition: You have a comma-separated list and want to break it into individual items — split does that, returning a list. Conversely, you have a list of items and want to combine them into a single string with a separator — join does that. Note: join is called on the separator string, not on the list.

5. Replacing

text = "I like cats"
print(text.replace("cats", "dogs"))   # "I like dogs"

Intuition: You want to swap one substring for another throughout the entire string. replace returns a new string with all occurrences replaced (you can also specify a maximum number of replacements).

6. Counting and Checking Type

word = "mississippi"
print(word.count("s"))        # 4
print(word.isdigit())         # False
print("123".isdigit())        # True
print("hello".isalpha())      # True
``` …