What is the difference between "password" and "passcode"?

A Passcode is a four or six digit number or some combination of those that is used to unlock the iOS device when you want to access it.

A Password is something specific. Your Apple ID has a specific password used to protect your account. Many apps and website will also have their own specific password to protect the act they provide access to.

If you are having problems with your Passcode or the Password for your Apple ID reply here and let us know which one and describe the problem.

Apple ID uses a password.

iOS based devices use a passcode > Use a passcode with your iPhone, iPad, or iPod touch - Apple Support