lastlog is a program available on most Linux distributions. It formats and prints the contents of the last login log file, /var/log/lastlog (which is a usually a very sparse file), including the login name, port, and last login date and time. It is similar in functionality to the BSD program last, also included in Linux distributions; however, last parses a different binary database file ([[Utmp|/var/log/wtmp]] and /var/log/btmp).
Lastlog prints its output in column format with login-name, port, and last-login-time of each and every user on the system mentioned in that order. The users are sorted by default according to the order in /etc/passwd However, it can also be used to modify the records kept in /var/log/lastlog.