I think knowledge is key to becoming a millionaire at a young age. While some are exposed to certain money making strategies earlier, others bask in ignorance until they are older. I think if we utilize the knowledge we acquire early enough, we can become millionaires.This is a dream of majority which only comes to reality for minority. Becoming a millionaire at a young age is a great feat. The background and mentality is also a contributing factor to achieve this feat. There are really no particular rules attached with this.