Perhaps unexpected, the time command, doesn’t actually give you the system time (use date for that). What it is does is “time” how long something takes to run (so a different use of the word time).
So for example, let’s say you are doing a mysql import, you can prepend it with time to find how long it took to run:
$ time mysql -u user -p db < import_file.sql
A quick and useful benchmark, even if it only lets you know how long you have to go make a coffee 🙂