Displaying GIFs is pretty easy. For example...
Download the big moose graphic in the upper left corner of this page and save it as "moosebig.gif" in the same directory where you'll create a Java
applet. In this directory, create a text file named FooApplet.java and edit it to have these contents:
Compile the .java file. Now create a new text document and name it MyApplet.html. Edit it to have these contents:
Save the html file and view it using the appletviewer (appletviewer MyApplet.html) or with a web browser.