Passwords
To make a new password simply use the sudo passwd username command from the command line. But you need to comply some rules before a password is accepted. Sometimes you need a simpler or shorter password.
To set up a simple password, I tried the simple sudo passwd username
method, but it failed on my Ubuntu 16.04 LTS.
So I removed the obscure
option from /etc/pam.d/common-passwd
config file, but it still failed.
So I also removed the obscure
option from /usr/share/pam-configs/unix
config file. And then it worked :-)
beware that shorter passwords are less save.