/var/

/var/log/
/var/spool/cron/crontabs/
/var/lib/
/var/lib/docker
/var/lib/docker/volumes
/var/opt/

/var/cache/
/var/cache/apt/

 Related commans: apt-get clean

/var/lib/postgresql/10/main
/var/lib/mysql (See also: 50-server.cnf)

/var/www/ (See: Nginx)

See also

• FHS, /proc/, /proc/net/, /boot/, /run/, /dev/, /usr/, /var/run/, /etc/, /var/, /var/lib/ /var/log/, /var/www/, /opt/, /lib/, /sys/, /proc/kcore, /proc/sys/, /proc/sys/vm/, /snap/, /mnt/, /mnt/data, /var/opt/, /usr/bin/, /lib/, /proc/$PID/, /proc/self/
• Linux Logging: logger systemd-cat journalctl, syslog, rsyslogd logrotate, sshd logs, Logwatch, logcheck, Container logging, Journalctl logs, journald.conf, Docker logs, ts