#   
## Overview
The **`string.index()` method** is used to get the index of any character in a string in Ruby. This method returns the first integer of the first occurrence of the given character or substring.

## Syntax
```Ruby
str.index(substr)
```

## Parameters
**`str`**: This is the string that calls the `index()` method.

**`substr`**: This is the specified substring or character whose index we want to get.

## Return value
This method returns an integer value.

## Code example


# create strings
str = "Edpresso"

# get index of 
# substrings or characters
a = str.index("E");
b = str.index("ss");
c = str.index("p");
d = str.index("re")

# print results
puts a
puts b
puts c
puts d

## Code explanation
* **Line 2**: We create a string and initialize it.

* **Lines 6–9**: We call the `index()` method to get the indices of some characters and substrings.

* **Lines 12–15**: We print the results that were returned by the `index()` method.

What is string.index() in Ruby?

Finds the first occurrence index of a character or substring in a Ruby string.