Is it safety using a "username" and "password" with same character?

If you use the same username and password it would be easy to remember the password, but I don't think that it is a good idea. It is much too easy for other people to guess the password if you use the same characters. It is best to create a unique password every time. That makes to hard to remember the passwords if you join many sites, but I still think it is better to be safe than sorry. I keep my passwords in my handwritten notebook or write them by hand in my day planner.

definitely not. password should be something which is hard to guess by others. it's about our security so using the similar username and password is like waiting the chance to get hacked by hacker.it's stupid mistake. even the site always suggest us to use combination between letter and number to make it so private and safe