Find my password
If you really forgot your password, try writing down all passwords you used last year, and try them one by one. If you can't find it, nobody can.
If you can't get in a phone because you forgot your password, the only way in, is to reset the phone and setting up the phone from scratch. You will lose all data, like contact lists, notes, images, and all apps, you did not backup on a computer or in the cloud.
Setting up a password protection on a smart phone, was to prevent anyone without password to be able to access your data. Now you forgot the password, you are excluded to the information too.
If there was a general code to unlock every password, that would make the security a farce and worth nothing.
Apple can help you to reset your login, when you enter the correct password that belongs to your Apple ID. It will be partially on the screen. If you really messed up, setting up security, and lost unlock code and your Apple ID password. Only Apple can help. For that you have to take iPhone, invoice and prove of your identity (Passport) to the Apple store and hope they will unlock your iPhone. With iOS7 Apple made a very good security system. And while setting up the iPhone and the security, you are warned several times what to do to make sure you and only you could enter the system. Whatever you is told there is no bypass for the Apple security system.Be aware if Apple does reset your iPad, all data now on the iPad will be lost.