How to reset password on macbook

Turn the mac on while holding the keys 'command' and 'R'. Let go of these after 10 seconds. Now once you are in recovery mode go to Utilities > Terminal, then type 'resetpassword' as shown here. You will then get an option to reset your login password.

However, you will no longer have access to any other passwords stored on your Mac (Keychain) as it's locked with your forgotten password. Instead, a new one will be created which you can save passwords to. To exit recovery mode go to  > Shut Down, then turn the mac on normally.

Hope this helps,

rs09