The WTV format is a format by Microsoft and used for recording TV content in Windows Media Center. It can contain MPEG-2 or MPEG-4 as video codec and multiple audio codecs.
GIF is an image format that supports animated images. It can adapt 256 colors and uses lossless compression technique to contain images. It can also contain texts. It can contain low sized image animation. So it is frequently used in web publishing. It applies LZW compression algorithm to compresses low colored images.