IDV is the Integrated Data Viewer. Download here a short presentation of the tool.
To download IDV you may want to visit the developer website, Unidata:
Under download, you have differente package: to download IDV you need an account on the Unidata site. Register or ask for an account to the tutors.
Once you are logged in on the site, you can download and install the package. At the moment of this writing the version is 4.1:
IDV is a standalone viewer, so it will run on you local machine. Then you will let IDV connect to local or remote datasets. The Unidata Workshop is a good starting point to take confidence with IDV: