Q:

ascii characters to avoid in passwords

I recently started web development using django. While working on the user registration page, 
I was researching few things on the password.
Web sites generally place restrictions on the characters that can be used in password. For example spaces or angle brackets cannot be used . 
Because all inputs are cleaned and hashed before they are stored to the Database, using any printable ascii characters in password shouldn't really be a problem... right? or am I missing anything.

A:

You're not missing anything. Most of the time, the only reason to exclude spaces or any printable ASCII character is because of bad coding.
The other times, it's for disambiguation of similar-looking characters for autogenerated passwords (I-l-1, O-0, etc.).

