What are the differences between wp_users and wp_usermeta tables?

What are the differences between the wp_users and wp_usermeta tables?

I use the Email Login plugin and I just noticed that if a user changes his email in the profile page, it is saved in the wp_usermeta table and not in the wp_users table,

This is a problem because the user has to use the first email to login successfully, and if he used the new (changed) email he can’t get access.

Can anyone explain why and how I can save the user email in the wp_users table?

wp_users is the primary table, with a fixed list of columns.

wp_usermeta is an additional table for storing arbitrary information (custom fields).

The wp_users table already has a user_email column, so I don’t know why the plugin uses wp_usermeta. The best person to ask would be the plugin author himself.