Is a media container format designed for streaming over the Internet. Used on popular video hosting sites. Video is usually stored in h.263 and h.264 formats, audio is a in MP3 or other less popular codecs. FLV-file format is a bit stream, which provides high-quality image even at low bit rates.
GIF is a format for the exchange of images. It is a popular format graphics. Capable of storing compressed data without loss of quality in the format of not more than 256 colors. GIF format was developed in 1987 (GIF87a) by company CompuServe for transferring raster images over networks. In 1989, the format has been modified (GIF89a), have been added support transparency and animation.