Tif File Extension
Tif is a file extension of Tagged Image file. It can be viewed by Photoshop or Acdsee.
In contrast with the normal Jpg images, Tagged image files include alpha channel. Besides its image quality is much better than the other versions. It can be created by a software such as Photoshop. You can view those files with any image software.
It is inconvenient that keeping images (especially those which are used for printing and press) with a JPG extension. Because it has bad influence on image quality. In this case you can easily use TIF or TGA file formats.
There are different options to download as a Image Viewer. You can check it on internet.
What needed to Open Tif file extensions.
Photoshop, Acdsee, irfan view
Links about Tif file extension