How to use

Answer 1

This is a lesson from python, you can find here more about strings:
https://www.sololearn.com/learn/Python/2274/

Answer 2

strings in programming is very useful.if we take real world example when you create a real programme or software anything then you use string in thousands of time.e.g
Let you create a simple video editor desktop app.when user open first time a box is pop up which is terms and conditions and you need to agree with it.Now here terms and condition are written in programme in string data type.thousands of word or letter you see in app basically is written in string data type.