There are over a two dozen graphic file types in use today. Netscape only supports viewing GIF and JPG images. If you download a .gif image and need to convert it to the .tif format to use with Powerpoint or another software program, a conversion program would be needed. However, converting from one type of file to another is easy with use of a conversion program.
Most graphics viewing programs include conversion capabilities.
While there are a number of good graphics packages available that range from easy to use beginner's packages to extensive graphic art programs, two good mid-level packages are Graphic Workshop for PC's and Graphic Converter 2.2 for Macs. If you don't already have a graphic viewer you can download the above mentioned one that is correct for your platform by clicking on the links below. Graphic Converter and Graphics Workshop are both shareware. There are German and French language versions available as well. In addition to viewing and conversion, both programs allow manipulation of the image with sizing, drawing, and shading tools.