Determine the version of MySQL server

How do I tell what version of MySQL server that I am running?

To determine the version of the MySQL server running on host ‘elephant’ use:

mysql -h elephant -V mysql Ver 12.21 Distrib 4.0.14, for pc-linux (i686)

The MySQL version indicated by the output line above is 4.0.14. To determine the version of MySQL running on the local host, use the same command without the ‘-h elephant’ option.