You can easily change your password in your user profile. If you're an admin you can reset an end-user's password (see Resetting user passwords).
An email confirmation is sent when an end-user password is changed via:
- Agent interface
 - Password reset link
 - API
 
Note: If your password expires before you've had a chance to change it, you'll be redirected to a
      Forgot password flow when you try to sign in. Follow the onscreen instructions to reset your
      password.
To change your password
- In your user profile, open the Security Settings tab. 

 - Click Change in the Password section.
 - Enter in your Current password, then enter your New password twice.
            Note: The new password must match or else your password will not be saved.
 -  Click Change password. 
Your password is updated. You will receive an email from Zendesk Support notifying you that your password has changed.