In Linux Mint 17.3, ncal should already be installed by default, but if not, you can install it from Synaptic by installing the bsdmainutils package, which contains a collection of command-line utilities.
sudo apt-get install bsdmainutils
Running ncal is a s easy as typing its name at the command prompt:
Entering ncal by itself shows the current day of the current month and year.
If you wish to see a horizontal layout, use the -C option.
What is the difference from cal?
Linux also includes the cal program, which also displays a calendar, so what is the difference?
They are mostly the same. ncal will do everything cal can do. The most apparent difference is the default vertical layout of ncal so an entire year can be shown in an 80-column terminal in fewer rows than cal.
With the vertical format, ncal displays four months in a row while cal shows three months in a row.
Entering man ncal will show many, many options for calendar customization. Options may be combined.
ncal -y 2015 -C
ncal -A 3
ncal -y 1900 | lolcat
ncal -m 10 | cowsay
There are a number of options possible with ncal, including country codes, so have fun and experiment!