Cal

Cal is a command which displays the calendar for the month and the year.

Syntax
cal [month] [year] 

[month]
 * Specifies the month for you want the calendar to be displayed. Must be the numeric representation of the month. For example February is 2 and November is 11.

[year]
 * Specifies the year that you want to display.

Examples
$ cal displays the calendar for current month. $ cal 11 2001 displays the calendar for November of 2001.

Provided by
Most (all?) Linux distributions incorporate this from the [util-linux] project.