[ubuntu] Can you guide me to instal this ps2pdf package

I have some .ps files that must be converted to .pdf, some googling leads me to a standalone installer package from: http://manpages.ubuntu.com/manpages/.../ps2pdf.1.html
and now I have this file: "ps2pdf.1.gz" in my "download" folder. This file is as large as 1.2 kB (1,196 bytes) and I want to install this package.

Now what should I type in the terminal to install this ps2pdf package?
Thank You.