The following are the system tasks and function provided by Verilog.
$bitstoreal
$countdrivers
$display
$fclose
$fdisplay
$fmonitor
$fopen
$fstrobe
$fwrite
$finish
$getpattern
$history
$incsave
$input
$itor
$key
$list
$log
$monitor
$monitoroff
$monitoron
$nokey