Is there any practical example or demonstration for the use of lists,sets and hashes in our dailife

Answer 1

Websites you register for most likely hash your password for security.

Demonstration:
- User visits site
- User registers with password "123"
- Website hashes it
- Attacker somehow manages to view the database rows
- Attacker will see your password as it hashed and he/she won't know what it actually is.

Answer 2

thanks a lot for replying to my question,ur answer is very helpful to me in understanding the usage of learning them and their importance

Answer 3

Also don't forget that the "normal" arrays do have a fixed length that is specified by you when you initialize said array. That's a huge problem when you are dealing with data that you can't just figure out how much space it will need to be stored. With an array list you can bypass this problem as it's dynamic.