All important string operations.

Case Conversion

```python text = "Hello World"

print(text.upper()) # HELLO WORLD print(text.lower()) # hello world print(text.capitalize()) # Hello world print(text.title()) # Hello World print(text.swapcase()) # hELLO wORLD ```

Finding and Counting

```python text = "Python is awesome. Python is easy."

Find position print(text.find("Python")) # 0 (first occurrence) print(text.find("Python", 10)) # 19 (search from index 10) print(text.find("Java")) # -1 (not found)

Count occurrences print(text.count("Python")) # 2 ```

Replacing

```python text = "I love Python"

Replace new_text = text.replace("love", "enjoy") print(new_text) # I enjoy Python

Replace first N occurrences text = "ha ha ha" print(text.replace("ha", "he", 2)) # he he ha ```

Splitting and Joining

```python # Split text = "apple,banana,orange" fruits = text.split(",") print(fruits) # ['apple', 'banana', 'orange']

Join cities = ["Miami", "Austin", "Denver"] text = ", ".join(cities) print(text) # Miami, Austin, Denver ```

Trimming

```python text = " hello "

print(text.strip()) # "hello" print(text.lstrip()) # "hello " print(text.rstrip()) # " hello" ```

Checking

```python print("hello".isalpha()) # True print("123".isdigit()) # True print("hello123".isalnum()) # True print("HELLO".isupper()) # True print("hello".islower()) # True ```

Remember

- Strings are immutable - Methods return new strings - Use split() and join() together