bspraj on "Web site hosting"

Hi,
I am having a web site prithvirajbs.com & I have been maintaining the same on my laptop where I have been downloading the latest versions of WP.
Now I want to maintain another web site nabkarnataka.org from the same laptop. My question is whether I have to install wp again for the new website or can I use the existing one. I shall be grateful for guiding me on this.
Prithviraj