Log File
A log file is a file that keeps a registry of events, processes, messages and communication between various communicating software applications and the operating system. Log files are present in executable software, operating systems and programs whereby all the messages and process details are recorded. Every executable file produces a log file where all activities are noted.
Login
A login is a set of identifications used to validate a user: this generally involves a username and password that allows a person to log in to a computer system, network, mobile device, or user account. A login might contain further information, such as a PIN number, passcode, or passphrase. Logins are usually used by websites, computer applications, and mobile apps to verify a customer's identity. They are a safety measure aimed to avoid illegal access to private data or assets.
Login Authentication
The process that recognizes and validates a user's identity is known as login authentication. A common example is having to enter both a username and password into a website in order to gain access to an account.