Prevent editing of user information

Hi,

I am new to Drupal and have been searching and reading for weeks with no resolution found, how can I prevent a user from editing their own details contained on the User node...details such as email, name, or custom fields added using the Profiles module?

This information will be employees and I do not want them to be able to edit any details, only the Admin should have access.

I truely appreciate any help.

Thank you in advance,
James