I bet that the phrase **"Why should I count the number of letters in the string? I want things to get easier..."** has crossed your mind. However, Python has a billion built-in functions, and finding the string length `len()` is one of them and it may be one of the most commonly used in programming. Take a look at the example, and everything should become clear:


 ```
Input:
string = "Practice is the key to success"
length = len(string)

print("Here is the string:", string)
print("And its length is", length)

Output:
Here is the string: Practice is the key to success
And its length is 30
``` 


>Pay attention to the `len()` function; it counts the **number of items** within the string, but you can call it the length of the string.

Numeric data types are crucial in Python, so it is important to start with them. Here you will work with simple math operations and find out the purposes of learning different types of numerical data.

The main goal of this section is to clarify the boolean data types; it's a sub type of numeric data, but indeed it is more challenging. Since it is always better to excel in the more difficult topics, this section is a valuable part of your curriculum.

Strings are a way for us to implement your phrases in Python, that is, to give instructions to users who are the target audience of your program. Indeed, it is always better to be able to work with strings because they should be used in your code. You'll understand why soon.

This chapter consists of practical tasks that combine all the examined topics together with a bit of theory.