Also, your password protects your ability to locate or remotely erase your device using Find My iPhone. If you forgot iCloud password, you are unable to access these files. Your iCloud password protects your personal files on iCloud, such as personal photos, contacts. ICloud account and password is needed when you want to log into iCloud on your Mac, iPhone, iPad or iPod.
In this case, to reset iCloud password is to reset Apple ID password.
Generally speaking, your iCloud account is your Apple ID, which is an email address you used.