My Apple computer is about 6 years old. The original and current apple password is 5 letters, all lower case, plus one digit. It opens my computer and I consider it my apple password. Unfortunately, when on my iPhone or iPad, and I am asked for my "apple password" it does not and cannot work (it doesn't fit password requirements). If I try to create a new password, for my iPhone and iPad, I cannot make it happen, no matter what instructions I have followed in the support information. My husband who has all the Apple gadgets and computer, has tried but is unable to assist me.
If you have ever signed up for an Apple ID, which is the user name you use for everything at Apple including iCloud, you can recover/reset your password at this page:
This is not the same as the password you used to lock down a user account on a computer running OSX.